Four days after their dominant 1-2 at Monza, Mercedes are back on the racetrack as both Lewis Hamilton and Valtteri Bottas participate in a Pirelli tyre test at Paul Ricard on Thursday.

With a deadline looming at the end of the month for the Italian supplier to submit their tyre construction for next year, the two-day event at the host venue for next year's French Grand Prix is the final time Pirelli will get to evaluate their different prototypes.

The significance of Mercedes and particularly their race drivers taking part is, last year during the testing for the wider tyres that were introduced this season Hamilton rejected the chance to test for Pirelli believing it would be of little value, however, Sebastian Vettel completed over 2000km with Ferrari with many claiming that gave him an advantage over the Silver Arrows. 

Indeed, the tyres remain a key area where at high degradation circuits or in high temperatures the Scuderia do hold an edge over their main rivals.

The decision to test with both drivers, as Bottas will be driving on Friday, suggests Mercedes have learnt from the experiences of this and Hamilton too acknowledges it is a break from his usual view on testing

"I will be doing the test this week, which is very rare for me because l am not a tester," he said over the weekend at Monza. "I am looking forward to it, l offered to do it."

Two more tests await after this one at Paul Ricard, with Force India and Sauber staying on after the Mexican Grand Prix to complete two and three days running respectively and McLaren will also complete two days of running following the Brazilian Grand Prix at Interlagos.

Though these will take place after the construction deadline, Pirelli can still test various compounds, with their Head of F1, Mario Isola recently suggesting a sixth type of slick tyre could be introduced for 2018. 

His victory on Sunday may have been a comfortable one, but Lewis Hamilton is vowing not to relent up in the final seven races insisting the battle with Ferrari remains as fierce as it has all year.

The triple world champion inherited the championship lead after his win at Monza as Mercedes finished well over 30 seconds clear of Sebastian Vet`tel at the Scuderia's home race, moving three points clear of the German with his third win in four races.

Indeed, looking back over his recent results, the Briton admitted the first of that trio of successes was the catalyst that he used to move up another level.

"Silverstone was a real empowering weekend," Hamilton said. "It kind of sparked a forest fire within me, and that’s hopefully reflecting in my driving and the way I'm working with my guys.

"I felt more heart and passion within myself, I've found more inside myself in the last three or four races," he continued. "My heart is the engine and the power and the force behind what I do. My mind is really like the rudder, and I feel like it's really steering me in the right direction."

What has also helped is the last two circuits at Spa and Monza have better suited Mercedes over Ferrari due to their emphasis on power and the 32-year-old praised the efforts of his team as they continue to push development.

"It’s obviously an incredibly exciting season, and the last two races have been incredibly strong for us as a team," he commented. "We’ve gone from strength from strength and really shown real strength and depth. I think it’s the way we have come together in this second half so far is exceptional but it’s still close and there’s still a long, long way to go."

The final destiny of the F1 championship this year could well be decided in the next three races, as Singapore, Sepang and Suzuka are all circuits which from the data, should suit Ferrari more than particularly last two circuits.

"The fight will continue," he predicted. "It’s been a long, long time that Sebastian has been leading the championship. With all the ups and down to now be just slightly ahead is a great feeling.

"He’s generally had a relatively comfortable lead most of the year. I think sometimes at 20-something points. I’d imagine that I’m, what is it, three points ahead? I’ll take that and I’m happy with that. I guess the plan for the next races is to try and extend that."

Revealing how he expects to do that, he concluded: "[By] giving it absolutely everything we’ve got. It’s going to continue to be really close between us all but yeah, absolutely. Beast mode all the way to the last chequered flag!"

McLaren CEO Zak Brown has revealed that the team have a 'Plan B and Plan C' if Fernando Alonso chooses to leave.

Alonso, whose contract expires at the end of the year, has grown frustrated with McLaren's ongoing lack of competitiveness.

The Woking outfit are looking to seal a divorce from struggling Honda and switch to Renault power for next year, which could convince Alonso to stay.

Yet if the Spaniard feels a long-awaited podium return remains out of reach, he may well move to IndyCar.

Asked what McLaren would do if Alonso jumped ship, Brown replied: "We've got another plan.

"He hasn't signed with us yet, negotiations are ongoing and going very well. 

"But you've got to have a Plan B and C in the event that you don't reach an agreement, and we've got those plans."

However, despite an impressive outing in the Hungary test, the team do not view young prodigy Lando Norris as a viable alternative.

Brown says it is likely Norris will race in Formula 2 next year to garner some vital experience before graduating to the top tier.

"Our current plans are to put him in Formula 2," he said.

"Certainly I think he's fast enough to be in Formula One, but you need to make sure not to rush things and give him enough experience.

"So he's definitely our star of the future and I don't think we'd put him with another Formula One team."

Red Bull motorsport advisor Helmut Marko has re-ignited speculation that Carlos Sainz could leave junior team Toro Rosso at the end of this season, suggesting he wouldn't be "surprised" if the Spaniard was elsewhere.

The 22-year-old's future appeared settled after the brief spat with team bosses over the Austrian Grand Prix weekend. On the Thursday at Spielberg, he told reporters a fourth year in his current seat was "unlikely" only for Marko and senior team boss Christian Horner to in effect confirm him for 2018 by saying there would be no way Sainz would be let out of his contract.

Since then, speculation has been quiet but the tone did ease a little when Horner later claimed Red Bull would listen to "significant offers" for the driver and now Marko, who is known for his straight talking, has done likewise.

"It's difficult to talk about 100 percent in Formula 1," he told Canal 1 Latin America when asked if Sainz's future with Red Bull was certain.

"I would not be surprised to see him at another team because I know what his contract is," he added, "but only we can make it possible."

Indeed any deal for the highly-rated talent would have to be done with Red Bull rather than the driver but there is one ongoing situation that would seem to open that door.

Last year, Renault was one of the first teams to express an interest in Sainz only to have their approach rebuffed, but with ongoing talks between the French manufacturer, McLaren, Toro Rosso and Honda could see him move to the Enstone team in an agreement that sees Renault end their engine supply contract with Toro Rosso and switch to McLaren.

If that was not the case and McLaren remained with Honda, should Fernando Alonso leave, then his fellow countryman is considered an alternative to replace the double world champion.

The situation is very complex, but for Marko to suggest a Sainz move is not impossible would indicate something is happening behind the scenes.

Force India Deputy Team Principal Bob Fernley insists the team want to retain their current line-up of Esteban Ocon and Sergio Perez for 2018 despite recent tensions and interest from elsewhere.

Both drivers are likely to continue with the current fourth-placed team in the Constructors' standings as Ocon signed a multi-year deal when joining from Manor at the end of last year and Perez was reportedly close to a deal before the Belgian Grand Prix but incidents in Canada, Baku and Spa have led to questions as to whether their partnership is tenable. 

New team instructions were introduced from Monza, though not needed, and Fernley insists though it is a difficult situation for the Silverstone outfit, their competitiveness and results are worth it.

"We'll do everything in our power to maintain the driver line-up we have today," he told Autosport. "We're in a very fortunate position in that, like the top three teams, we've got two super-talented drivers, and we're going to need that in order to battle for fourth place in 2018, or hopefully even go higher.

"The last thing we want to do is to lose talent."

Ocon's performances, in particular, have caught the eye in his first full season as the Mercedes junior has scored points in all but one of the 12 races so far and that has led to some interest from Renault, the team he was with as a reserve driver before joining Manor from Spa.

"Esteban is contracted with us effectively for three years, but two of them are absolutely secure," Fernley claimed, rejecting any idea of the 20-year-old departing. "From a contractual point of view it's clear, and I don't think Esteban has got any ideas of wishing to go anywhere else at this point.

"You've got to remember that we identified the potential of Esteban some time ago," he added, referring to how they chose Ocon over Pascal Wehrlein for this season, "and we obviously took the opportunity where others didn't, including Renault, to sign him last year.

"We've now got the benefit of that, and we want to make sure that we optimise that."

Porsche appears more positive about the idea of returning to Formula 1 as an engine supplier in 2021, following more talks over the engine that shall be introduced at the end of the current Concorde Agreement.

The German manufacturer has been linked with an F1 project alongside their future entry in Formula E, which they will do from season six, a move that came at the expense of their LMP1 program in the WEC.

A Porsche comeback would also signify a return for their parent company Volkswagen, with their Motorsport boss Bernhard Gobemeier recently revealing the staff from their WEC operation are working on a new high-efficiency racing engine but wouldn't reveal what that engine was for.

In the same comments he made to Auto Sport und Motor and we reported, Gobemeier was very critical of the state of F1 and what he saw as a "dangerous path" it was heading on due to out of control spending. 

And, talking to Motorsport.com after the latest meetings in regards to 2021, Porsche's Financial Chief Luts Metschke admitted cost would be a major factor in the company's final decision.

"Absolutely. We have to cut costs in F1 and it's a good way to reach this target," he said referring to the plan for a cheaper, simpler engine.

When weighing up how likely it was Porsche would give an F1 project the green light, he added: "F1 could be one of the right places.

"As you know Formula E is very important for us now, and F1 is always a good topic to think about. I think we are in quite good discussions regarding the new engine."

Porsche is just one of several names reportedly interested in joining the F1 grid if the new engine rules are to their liking with Cosworth already poised to join and Aston Martin also touted.

Ferrari Team Principal Maurizio Arrivabene has made it clear both Antonio Giovinazzi and Charles Leclerc would have to excel in Formula 1 machinery before being considered for a seat with the Scuderia.

Giovinazzi had his first opportunity to do so when he was thrust into the Sauber car for the first two races of this season, replacing an injured Pascal Wehrlein. Though the Italian showed good single lap pace and finished 12th in Australia, China would be a different story as he crashed in the cold, damp conditions in qualifying and the race.

As for Leclerc, he has dominated the F2 season claiming pole at all but two events and winning five times. As a result, the Monegasque will look to wrap up the title at his first attempt when the series heads to Jerez for a standalone event next month.

Both are set to complete a number of Practice 1 sessions between now and the end of the year at Haas and Sauber respectively, with the likely outcome of one joining Marcus Ericsson at the Swiss team for 2018.   

Traditionally, however, Ferrari juniors have had trouble completing the ladder and racing for the Italian team compared to say the young drivers at Red Bull. Felipe Massa was one that did but Sergio Perez eventually left to join McLaren in 2013 and Jules Bianchi would suffer his tragic crash but also found it hard to move up from Marussia despite two impressive years.

It was hoped the arrival of Arrivabene and a change in the Ferrari mentality would change that but as the retention of an often underwhelming Kimi Raikkonen for 2018 proved that doesn't seem the case.

"[Sebastian] Vettel and Raikkonen went through the last three years with great co-operating within them. They feel very good together, being part of the team and translating this spirit to the overall team," Arrivabene said defending the decision. "I think we don’t find any reason why not confirming them together."

He would offer hope to the likes of Leclerc and Giovinazzi that they can fulfil their dream but, as you would expect, set a very high requirement for them to meet if they wish to do so.

"They are growing," Arrivabene said. "Our objective is, of course, to grow up young drivers and maybe to see them in the future with us.This is the final goal but, before that, they need to demonstrate in Formula 1 that they deserve it."

Williams Technical Director Paddy Lowe praised the performance of Lance Stroll as he produced an excellent performance in both qualifying and the race at the Italian Grand Prix.

The Canadian hasn't been able to push on from the high of his first Formula 1 podium in Baku in June as the British team has struggled to optimise the performance of the FW40 but in the rainy conditions in qualifying, which usually don't suit Williams, the 18-year-old would finish fourth quickest overall, beating the two Ferraris and Valtteri Bottas. 

Grid penalties for the two Red Bull drivers in front would then see Stroll start second for Sunday's race making him the sport's youngest front row starter in history beating a record set by Max Verstappen last year.

Though a tentative race saw last year's European F3 champion fall back to seventh, the former Mercedes boss was very pleased with how he once again capitalised on an opportunity to show his potential.

“I think you’ve got to remember he’s not only a rookie, but he’s only 18. He hopefully has a long career ahead of him,” Lowe said. “I remember where I was at when I was 18 and it was pretty much nowhere. I just find anything that somebody can do at an age of 18 really, really impressive. It’s very early."

Stroll's performance was also another answer to his critics, who scolded the decision to promote him and blamed it purely on his father's financial backing  

“Lance has had some struggles this year, but that’s to be expected in anyone’s first year in F1, especially coming in so young," Paddy added, "but it’s great to see that he’s finding his moments to display his talent, and I hope he can build on that."

Teammate Felipe Massa also had a better weekend as the Brazilian made Q3 in qualifying, by the end of the race, the two Williams cars were battling each other on track, with Stroll just finishing ahead but Deputy Team Principal Claire Williams admitted, after the Force India situation at Spa, it was a nervy final few laps.

"We absolutely let them race and that was probably more to make sure Perez didn't overtake Massa rather than put the pressure on Lance," she told Autosport.

"It was a little bit scary the last lap, but we have total trust in Felipe. He's an old hand, an experienced driver and he knows about taking team-mates off and the rules around that.

"We had some issues with both cars at the end with some overheating, so I'm glad to get them finishing seventh and eighth."

On Stroll's speed, Williams, who announced she would miss the remainder of the year after revealing she was pregnant, added:  "With Lance qualifying where he did, it's a testament to the performance he has.

"When he drove the car for the first time in the wet [in qualifying] and did what he did - it was fantastic.To have the car to come home where it did, it's a happy way to end the weekend."

The Head of Honda's Formula 1 operation, Yusuke Hasegawa, claims he is struggling to convince McLaren to continue their partnership beyond 2017 as a deal with Renault appears increasingly likely.

Bosses from the French manufacturer and the British team were seen leaving talks over the weekend at the Italian Grand Prix along with the Formula One Group's Motorsport Managing Director Ross Brawn.

Come Sunday, Executive Director at McLaren Zak Brown indicated an announcement would likely be made before the next race in Singapore, and Hasegawa's latest comments seemingly indicate a divorce is on the horizon.

"I'm still trying to make a good performance to convince them but I'm not sure it will be enough," he said. "Honda never give up on keeping this collaboration."

It has been another difficult few weeks for the Japanese engine supplier as their lack of performance meant McLaren was unable to compete for points at the high-speed Spa and Monza circuits.

Stoffel Vandoorne was also forced to take engine penalties at both races, while Fernando Alonso also dropped down in Italy but that was due to continued engine updates being brought which Hasegawa claims have made been done quicker and seen gains made. 

"It accelerated our development," he said referring to the impact of pressure put on Honda by McLaren. "It becomes motivational inside the factory. 

"Since Austria, the Spec 3 engine introduction, our development has accelerated and the rate of development is very good. We saw some performance gain with each upgrade so it's very encouraging."

The long-term beneficiaries of a McLaren/ Honda divorce could be Red Bull as their junior team Toro Rosso will swap supplier with the Woking outfit but senior team driver Daniel Ricciardo has backed McLaren to be more competitive should a deal with his team's current partner go ahead.

“Unfortunately Honda has not been able to make McLaren’s car fast with these engines,” the Australian said. “So I think if they put in a Renault engine or anything else, they will automatically be faster because the car itself looks very good.

“They should be stronger next year.”

The respective team bosses at Red Bull and Haas have offered differing views on whether the current grid penalties for exceeding engine and gearbox parts should be changed following a mess last weekend in Monza.

Of the 20 cars in the field, nine would pick up penalties for new engine elements or changing a gearbox out of sequence. So silly was the situation, some drivers who had penalties actually started ahead of where they qualified and grid girls and crews were seen having to be moved to the right position before the start due to the confusion.

It is not a new debate, with many believing the penalties spoil the races and are also bemused when it reads that a driver has picked up sometimes a 50-place+ grid drop when only 20 cars race.

Motorsport Managing Director Ross Brawn stated in the build-up that he wanted an alternative to grid penalties to be found and Red Bull team boss Christian Horner, who saw both his cars fall down after qualifying second and third was scathing in his criticism.

"It needs a serious look at to see whether there is a better way to penalise a manufacturer or an entrant as opposed to messing around with the grid," he was quoted by Sky Sports. "It is only going to get worse towards the end [of the season] and it would be a shame to see this championship decided on grid penalties."

The Briton also pointed to the situation for next year, as the already tight limit of just four of each engine component is set to shrink even further in an effort to save costs.

"What concerns me is that we are going to three engines for next year with more races," he said. "To me, that should be number one on the agenda at the next Strategy Group meeting.

"I tried to get it changed at a meeting earlier in the year but there was no support for it. I would hope that would perhaps be different with teams staring down the barrel of further penalties between now and the end of the year.

"Obviously the penalty has to be a significant deterrent because the whole point of this was cost-saving. But we're not saving costs because the engines are going on a world tour anyway. Maybe five engines is the right number rather than four going to three."

Haas F1 Team Prinicpal Guenther Steiner would disagree with Horner, however, believing a grid penalty was the best all-around solution the problem and kept the top teams, Red Bull, Ferrari and Mercedes in check.

"We did this for a good reason -- to have cost control," he claimed. "If you get only one grid position or something, again the big teams will go away even further because they would change everything, every time, evolve it and be faster. They would make up the grid penalties with being faster.

"Look at Verstappen, or Ricciardo, 35 [positions] and he still finished fourth... The big teams they can make it up and if we reduce the grid penalties, there's no point to do it. The again we would just spend more money because we don't care about the grid penalties as we would make it up."

He also rejected the notion of any unfairness about the current regulations to customer teams who bare the brunt of penalties for failures of parts that they didnt produce, with many pointing at McLaren's issues with Honda.

"Yeah, we did something wrong. We signed up with the wrong supplier," he said, referring to if Haas had a penalty due to a Ferrari-made part. "You live by your choices. If you make strategic decisions wrong, you are penalised as well. It sounds maybe funny but you live by your choices.

"If you go for certain reasons to a manufacturers because you like their price, or like this then you're responsible for it, it comes with it. If you are penalised it, for example the works team has no problems and you have all the problems then it starts to get iffy, but I don't think it's happening for the moment.

"We know the rules. Is it looking good or not? The penalties are given a reason because people are doing a bad job. It's not like they were penalised, they knew before and if they don't do a good job, or good enough, then that's what they get."