Lewis Hamilton secured a potentially crucial 70th career pole as his first time in Q3 proved just enough to beat Kimi Raikkonen in qualifying for the Malaysian Grand Prix.

The Mercedes driver had been struggling for pace throughout practice but with the additional engine modes and his single-lap prowess, Hamilton produced an incredible 1:30.076s to smash the lap record and take his fourth successive pole at Sepang by less than half a tenth of a second.

The reason why the result is potentially crucial is because Sebastian Vettel will start Sunday's race at the back of the grid as an engine problem from Practice 3 continued into the qualifying despite a rapid change of the Internal Combustion Engine between the two sessions. 

The German would get out onto the track, but midway through his warm-up lap suffered a turbo issue which meant he had to return to the garage where he would remain. 

Back at the front, Red Bull will fill the second row as Max Verstappen improved on his final lap to pip teammate Daniel Ricciardo into third and at the same time would wrap up the qualifying battle between the two drivers as he will start ahead for the 11th time this season on Sunday.  

While Hamilton overcame Mercedes' problems, Valtteri Bottas would not as the Finn was seven-tenths slower than the polesitter in fifth.

The absence of Vettel allowed an extra midfield car the chance to make it into Q3 and it would be McLaren who capitalised getting both drivers into the top 10. Stoffel Vandoorne would also enjoy rare success over teammate Fernando Alonso with the Belgian seventh and the Spaniard 10th albeit with just over one-tenth between them.   

Esteban Ocon would be the lead midfield car in sixth for Force India with Sergio Perez only ninth and behind the Renault of Nico Hulkenberg in eighth, as the Enstone team made progress from final practice.

The big losers would be Williams as Felipe Massa was only 11th and Lance Stroll 13th, a disappointing result on the weekend they received the latest engine spec from Mercedes and still couldn't make Q3.

Debutant Pierre Gasly was disappointed over the radio after his lap but was only a tenth-and-a-half slower than Carlos Sainz in his first qualifying session for Toro Rosso. The two junior Red Bull drivers will line-up 14th and 15th respectively.

Finally, the two Haas' and two Sauber's brought up the timesheet but will start ahead of Vettel who has it all to do from 20th place.

The recovery of the Ferrari driver in the race on Sunday will be one of the key stories to follow but, despite taking pole, his main rival Hamilton is far from guaranteed victory with Raikkonen and the Red Bulls likely to offer a stiff challenge.

Add the ever-present threat of rain and the final Malaysian Grand Prix is set to be quite the thrill ride.

Pierre Gasly says he would welcome rain during Sunday's Malaysia GP as he looks to score points on his Formula 1 debut.

Gasly, drafted in to replace the out-of-form Daniil Kvyat this weekend, could only manage 15th in qualifying but was just a tenth adrift of team-mate Carlos Sainz.

Toro Rosso may be struggling to stay in touch with their midfield rivals in Sepang, but Gasly has been satisfied with his efforts so far.

"I think today was positive and I'm happy – your first qualifying in Formula 1 is always a special moment and one I was really looking forward to," the Frenchman said.

"I tried to give my best and I think we made really good progress between FP3 and Qualifying. 

"I felt comfortable in the car in Q1 and then, in Q2, I kept on learning while giving my all and I'd say we can be satisfied with the result! 

"I now look forward to tomorrow, my first Formula 1 race and something I've been dreaming of since I was very young."

Rain is a constant threat in Malaysia, and Toro Rosso are notoriously strong in wet conditions. 

Points, then, are far from out of the question despite a difficult Saturday.

"You never know what can happen with the weather here," Gasly pointed out.

"If the rain and tricky conditions do appear, I will welcome it as I felt confident in the wet in FP1 on Friday and I'm sure it will make it all even more exciting."

Kimi Raikkonen led the way as Ferrari maintained their advantage in the dry at Sepang in Practice 3 but an electrical issue for teammate Sebastian Vettel left the championship contender needing an engine change going into qualifying.

In a tricky session for the German, his best lap would be compromised by poor tyre preparation but the problem, which struck with four minutes to go, would be of greater concern as he cruised back to the pits. 

The new engine being installed was set to be introduced in Japan but without enough time to find and fix the cause of the electrical problem the Scuderia took no chances and opted to change. It also now means Vettel has used all four of his allocated engines with six races to go including Malaysia.   

As for the final practice session, Ferrari remains the team to beat as Kimi Raikkonen matched his best time from Friday to top the timings with a 1:31.880s, less than two-tenths clear of his teammate.   

Daniel Ricciardo also equalled his mark from Practice 2 to claim third, just over two-tenths behind the pacesetting Finn as Red Bull continued to look the nearest challengers to the Italian team.

Mercedes took different paths in an effort to solve their problems from yesterday with Lewis Hamilton ditching upgrades brought this weekend while Valtteri Bottas stuck with the new aerodynamic parts.

The impact was negligible, however, with Bottas still almost half a second slower than Raikkonen in fourth with Hamilton dropping two-tenths behind in fifth.

On his 20th birthday, Max Verstappen had a scruffy session in sixth which included a collision with Jolyon Palmer at the final corner in the final minutes. The stewards are currently investigating to see if any blame should be apportioned. 

A tight battle between Force India and Williams is brewing with Sergio Perez, Felipe Massa and Esteban Ocon all covered by less than a tenth of a second in position's 7-9. Stoffel Vandoorne completed the top 10, two-tenths clear of McLaren partner Fernando Alonso.  

Renault appeared to struggle with Nico Hulkenberg only 14th and Palmer, who lost his brakes entering the final corner the run before his late incident with Verstappen, 17th. 

Toro Rosso rookie Pierre Gasly was within three-tenths of Carlos Sainz, as the junior Red Bull team was sandwiched between the two Renault's in 15th and 16th respectively

Romain Grosjean understandably gave the kerbs at Turn 12 a wider berth after his crash on Friday but would spin at Turn 14 which compromised his session and left the Frenchman down in 18th in front of the two Saubers that completed the order.

FIA race director Charlie Whiting has claimed poor welding was responsible for the drain cover which came loose and caused Romain Grosjean to crash, leading to the abandonment of Practice 2 at the Malaysian Grand Prix.

The Haas driver claims he was unsighted after his right-rear tyre exploded upon impact with the metal cover, which was lifted by the force of Valtteri Bottas' Mercedes driving over it on the exit kerb of Turn 12, and sent the Frenchman spinning into the wall on the outside.

“I’m fine, that’s the most important thing,” said Grosjean when asked how he was following a trip to the medical centre following an impact recorded at 17G.

More typically drain covers can be dislodged on street circuits or at new venues, meaning the incident on Friday came as quite a surprise to many on a track which has hosted F1 since 1999, albeit saw a new lap record set on Friday by the faster 2017 cars.

"There are quite a few of them around the circuit and at this particular place, there are five at intervals on the outside of T12," Whiting told Autosport explaining what occurred.

"That's a high-G corner with a massive load being put through, and what we have found is some of these drains are bolted down and some are welded down and welding is perfectly acceptable.

"I suspect the bolts which have been going into little sort of lugs on the receptacle, which is where the water goes, have probably broken and rather than replace the whole thing, they've thought, we'll weld it down.

"Quite evidently, the welds just gave up. It's as simple as that really. No one saw that coming."

A full inspection of all drains will now take place and those which are welded will be re-welded in time for Practice 3 on Saturday.

As for Haas, they have been given special dispensation by the FIA to ignore the curfew usually imposed on team personnel at every race, in order to fix Grosjean's car.

Though teams are allowed to break curfew twice without penalty, this will not count towards that as the governing body see what occurred as an exceptional circumstance in which the team and the driver were not responsible.

Sebastian Vettel has turned his focus onto making up as many positions as he can in Sunday's Malaysian Grand Prix after an engine problem meant he was unable to participate in qualifying.

The German had to cruise back to the pits with what was believed to be an electrical problem in the closing minutes of Practice 3 earlier in the day, with Ferrari changing the Internal Combustion Engine in his power unit as a result.

Though it was hoped that would fix the issue, the problems continued as his turbo was heard giving up on his first lap out of the pits in Q1 with his mechanics unable to find a solution in the remaining time.

The result is a first back-of-the-grid start since Singapore last year and what is likely to be another major blow to his championship chances with main rival Lewis Hamilton starting on pole.

“It's part of motor racing,” Vettel told Sky Sports describing his feelings after getting out the car. “I didn't do anything today, this afternoon especially so it's not something to feel that much about.

“For sure it's not ideal, it's not what you want, especially on a day when you feel you've got it in you, you've got it in the car. But unfortunately, we won't be able to prove that.”

Given the pace his Ferrari has shown in practice, a fightback to at least sixth is likely in Sunday's race at Sepang but the four-time world champion is remaining "open-minded" on his target.

"I expect we will get back to the leading group," he claimed. "I don't have an expectation in terms of a number but anything can happen. That's why we go racing!

"I want to make sure we achieve our best. We need to extract the maximum. Knowing the race here, the conditions, anything can happen. I'm open-minded."

Despite the disappointment, Vettel also praised the work of his crew to do what is often a three or four-hour job in just over two.

"We managed to do the change successfully in time. We thought we would be late but we made it, so the guys worked a miracle today, worked like crazy,” he said.

Ferrari could well now install a completely fresh engine for the race, as the P20 start would nullify any grid penalties for exceeding his allocation of four of each component in the power unit over the season.  

Sebastian Vettel is hopeful for a few more laps on Saturday morning to complete the setup work he was conducting before Practice 2 was curtailed following the nasty crash for Romain Grosjean in Malaysia on Friday.

The Ferrari driver is targeting further improvement despite setting the fastest time of 1:31.261s in the dry afternoon session, which is a new lap record around the Sepang Circuit and had the four-time world champion six-tenths clear of teammate Kimi Raikkonen and eight-tenths ahead of Daniel Ricciardo in the Red Bull.

Commenting on how the day played out, Vettel said afterwards: “This morning we had a bit of mixed conditions and there was not so much running. This afternoon it was better. The car seemed to be quite okay right from the beginning of the session."

Always aware of others that will almost certainly find more pace, however, the German was continuing to fine-tune his car into the ace simulation after his fastest time.

"[There is] still some things we must improve," he said. "We tried something new, but unfortunately we couldn’t complete our programme as we had wished to because of the red flag.

"It’s only Friday, usually the day when you spend time trying various things on the car. We would have liked to drive a little bit more, but overall it was a decent afternoon. We have a good car and it’s up to us to make it work in all conditions."

Further work will continue in the debrief for changes to make going into Saturday and Vettel hopes to find out more about those tweaks.

"We’ll see what we can do tomorrow," he added.

What will have buoyed the 30-year-old was the problems at main rivals, Mercedes, with championship leader Lewis Hamilton only sixth fastest and almost 1.5 seconds slower in the afternoon.

Unsurprisingly, such a gap has led to some querying whether Vettel can take a significant bite into the 28-point deficit he now faces after his retirement in Singapore, but he is staying cool for now. 

“If that's the case, then yes, but it's Friday afternoon," he claimed. "Things can change. We'll see what tomorrow brings."

Lewis Hamilton was left "grateful" for the work done by his Mercedes crew as the Briton would able to overcome difficulties in practice and clinch pole position for the Malaysian Grand Prix.

The sixth place he achieved in Practice 3 earlier on Saturday was the best had managed so far all weekend before qualifying, but when it came down to the serious business, the well-known additional power from the German manufacturer's engine plus Hamilton's incredible single-lap ability proved enough to just beat Kimi Raikkonen in the Ferrari.

Certainly his first lap in Q3, a 1:30.076s, sent a shockwave the pit-lane and even the triple world champion himself seemed amazed by the pace he was able to find.

"Today we had no idea how it was going to go," Hamilton commented afterwards."Somehow we turned it around, the engineers did such a great job yesterday, the car felt great for both Valtteri [Bottas] and I.

"It's a real surprise to be up here with these guys, but I'm really grateful," he added.

Though able to find the speed in qualifying, uncertainty over the competitiveness of the Silver Arrow on race day remains and Hamilton admitted he faced a big challenge to convert pole into a fourth straight win since the summer break

"Obviously we're going to have a tough battle with these guys, Red Bull, in particular, had great long run pace yesterday, and today I think," the 32-year-old said. "I'm hoping that our car has moved in the right direction for also the race run but we'll see tomorrow. It's a long run down to Turn 1 so lots can happen."

What will also be on the mind of the Mercedes driver is taking full advantage of the problem for his main championship rival Sebastian Vettel, as the Ferrari driver will start last following engine issues on Saturday.

"I'm sorry for whatever happened to Sebastian as obviously, he was very quick in practice,” Hamilton commented.

Across the garage, the joy was not shared by teammate Valtteri Bottas, as the Finn was seven-tenths off the pace and will line-up behind both Red Bulls in fifth for Sunday's race.

The two drivers took different routes on setup with Bottas using a newer specification package while Lewis reverted to an older design. The 28-year-old insists he was happy with his car as well but was frustrated by how much he's having to change over a weekend.

"We’ve had many, many difficult weekends this year, as a team and this weekend especially for me," he said. "I think we had, many, many times, approached the weekends in a way that led to the need of making many changes to the car.

"Starting the weekend like that is never ideal, you start on the back foot, you start searching and the same thing happened this weekend with the set-up. Still, the car wasn’t easy to drive, so I think the answer is still pretty far away."

There was also disappointment at his own performance too, as the two-time race winner this season has failed to get within half a second of Hamilton in qualifying since Hungary.

"As for me I’m really, really far away or, at least, that’s how it feels today," he claimed. "It’s tricky being such a big amount of time off the pace, as a driver it’s difficult to accept."

Red Bull duo Max Verstappen and Daniel Ricciardo admitted the team had work to do after being caught out by the deficit to Ferrari in dry conditions during Friday Practice at the Malaysian Grand Prix.

The two drivers dominated proceedings in the morning as a tropical downpour just before the start of Practice 1 led to a soggy start to the final Formula 1 weekend at Sepang, but once the weather had cleared, the situation changed dramatically with Sebastian Vettel putting the Scuderia on top, some eight-tenths clear of Ricciardo in third.

Verstappen was four-tenths further behind his teammate in fourth but had a sloppy lap on the Supersoft tyre to set his best time, including losing around half a second in just the final sector alone.

"We need to work hard on the car to improve," the Dutchman, who turns 20 on Saturday, said. "We need to see tonight if we can improve the balance of the car and then we can see if we can challenge the Ferraris. But they look very competitive."

His Australian colleague repeated Verstappen's comments and revealed the gap to Ferrari plus the lack of pace shown by Mercedes both went against his and Red Bull's predictions.

"I thought Mercedes would lead the pack and we would be a bit closer to Ferrari," he claimed.

Offering a little more insight into where in particular, the RB13 was struggling, the one-time race winner in 2017 added:"Short runs we need to improve the front grip and the long run we need to improve the rear.

"On the short runs it is simple things, we can add some front wing and be more aggressive on one lap with the tyre. On the long runs you have to look after the rears, with the temperatures so hot, just looking after that will be the key on Sunday."

Stoffel Vandoorne was left 'pleasantly surprised' after extracting every ounce of performance from his McLaren to qualify a career-best P7 at the Malaysia Grand Prix. 

Vandoorne, who claimed his best result of the season last time out in Singapore, impressively out-paced Fernando Alonso in Sepang and will start from the fourth row.

The Belgian took pride in a fine performance, but fears he will struggle to hold station in Sunday's race.

"We weren’t really expecting to be so high up the grid," the 25-year old said. "We’d hoped to get into Q3, but fighting for seventh was a pleasant surprise.

"In fact, my whole qualifying session went really well. I didn’t make any mistakes and pulled every sector on every lap. To qualify seventh on a circuit like this is probably about as good as it gets for us, so I’m very happy with my performance.

"We generally tend to be better over a single lap than across a race stint, so I think tomorrow will be tougher for us, but at least we’re in a position to race."

Racing Director Eric Boullier was full of praise for Vandoorne's efforts both on and off the race track.

"Both drivers have worked very well together to develop and refine our car package across the weekend, and today’s qualifying result really justifies their efforts," he said.

"Stoffel has driven superbly all weekend, and absolutely nailed it in all three qualifying sessions, achieving his best F1 qualifying position so far.

"Fernando wasn’t particularly happy with his final lap, but he still has a very good opportunity for tomorrow."

Weighing up his chances on Sunday, however, the double world champion believes rain is the only chance he has of staying in the top 10.

“We’ll try to gain some places tomorrow and defend from those behind us," the Spaniard said. "For sure it will be a difficult race and the rain would be our biggest ally. For sure in the dry, it will be difficult to score points, but we’ll do the best we can.

“We know we lose a bit of pace in the race, compared to our most direct rivals, like Renault, Williams and Haas, so we know it will be complicated to score points, but that’s the goal.”

Lewis Hamilton has claimed Mercedes will look to "find our bearings" after a bad Friday left the three-time world champions as the third best team at Sepang.

It was thought the two Silver Arrows were simply easing their way into the Malaysian Grand Prix weekend when they were only sixth and seventh in the wet Practice 1 in the morning but when the Briton and his teammate Valtteri Bottas repeated those positions in Practice 2, the alarm bells began to ring.

What was particularly concerning was how nothing really seemed to work on the Mercedes' as both drivers went off the track on the Soft tyre early in the afternoon and then neither could hook up a competitive lap time on the Supersoft compound later on.

The result was a 1.4-second deficit to pacesetter Sebastian Vettel and Motorsport boss Toto Wolff suggesting there was a "gremlin" in the car which needed to be sorted out.

“It's been a very difficult day," said Hamilton, echoing his boss. "I've been struggling with the car today, so we have to review and try to understand where we have gone wrong with the balance. We're hoping that we're able to find our bearings overnight and regroup for tomorrow."

Historically Sepang has never been a great circuit for Mercedes with just a single victory coming in 2014, but Wolff admitted he was surprised by how the performance of the car on Friday was so different to how it was on similar layouts earlier in the year.

"You can compare Malaysia a little bit to Silverstone, probably, where we've been very good," the Austrian commented. "We've been very good in the high-speed, [but] we are not at all good in the high speed here.

"There's a fundamental issue in the car that we need to find out. They are very complex, so it can be a tiny detail."

What was equally concerning was the admission from Valtteri Bottas that his car wasn't actually feeling too bad on the circuit in terms of overall balance and setup.

"It's just a question of overall grip," he added. "We're definitely lacking some performance, it seems like Ferrari and Red Bull are very strong, so we have some work to do if we want to be on the front row tomorrow.

"The key area we are going to need to focus on tonight will be getting the maximum out of the tyres over one lap."