Postpublished at 02:35 Greenwich Mean Time 27 March 2015
Ben Edwards
BBC F1 commentator
"The team asked Lewis to bring the car to a halt after he reported some sort of click in the back."
Hamilton fastest in second practice, Raikkonen 2nd
Hamilton experienced engine and telemetry trouble
Champion completed few laps
Merhi and Vettel spin, Kvyat has engine trouble
Relive both P1 & P2 in 'Live Coverage' tab
Gary Rose
Ben Edwards
BBC F1 commentator
"The team asked Lewis to bring the car to a halt after he reported some sort of click in the back."
Lewis Hamilton walks alongside the recovery vehicle as his Mercedes is removed from the circuit. He then hitches a lift off a scooter back to the paddock and that looks like it could be the end of the session for him. Not ideal for the world champion.
It looks like a possible mechanical problem as marshals wheel the car off the track. Lewis Hamilton clambers out and watches as the recovery truck trundles over to remove the Mercedes.
I've not mentioned Lewis Hamilton, he hasn't done a flying lap yet, but he has just popped up on the television feed, and it is not for a good reason - his Mercedes is stock still on the circuit at Turn 9.
Nico Rosberg takes his Mercedes off track briefly at turn 9 but recovers to go fastest of all so far with a 1:40.973.
Out in the Sauber for first practice and making his Formula 1 grand prix weekend debut is is Ferrari protege Raffaele Marciello.
The Italian has been a member of Ferrari's young driver programme since 2010 and is Sauber's reserve and test driver for 2015. He won the Formula 3 European Championship in 2013 and finished eighth in GP2 last year.
He is driving Felipe Nasr's C34 today and he clocks a 1:45.259 with his first timed effort.
Dan woods: have manor the least amount of sponsors ever? #pluckybrit!
Max Verstappen, 17, became the youngest-ever Formula 1 driver when he debuted at the Australian Grand Prix.
It did not play out as he would have hoped, though, as his race was ended on lap 34 as smoke poured out of his Toro Rosso.
He can still make history this weekend, as F1's youngest points scorer. He's so keen to do well this weekend that he was getting a feel for the circuit in the fan zone driving the simulator earlier this week.
Valtteri Bottas goes for his first flyer of the weekend in the Williams and it is better than Marcus Ericsson's effort, a 1:43.432, but his stay at the top of the embryonic timesheet is brief as rookie Max Verstappen puts the Toro Rosso into P1 with a 1:42.725.
Just over 15 minutes into this session and we have our first timed lap, a 1:44.483 from Marcus Ericsson.
Roberto Merhi is out for his first run for Manor but there is fair bit of spluttering from the car as it struggles around the circuit. He just about manages to get it back to the pits.
The rain is a regular feature at the Malaysian Grand Prix and it looks like it will be no different this weekend, with showers a feature on the forecast on all three days. Have a watch of our video for the full forecast with BBC weatherman Ian Fergusson.
Stowe: Always find the magic of this track is the weather! What are the chances of a wet race on Sunday?
A trouble-free installation lap for Fernando Alonso as he gets a feel for the McLaren once again.
He had a slight wobble with the steering as he navigated the first turn, but nothing major as he gets the MP4-30 back to the McLaren garage.
Andrew Benson
Chief F1 writer in Sepang
"Fernando Alonso is not the only driver returning from an injury this weekend. Williams's Valtteri Bottas also missed the first race of the season, in his case because of a back injury sustained in qualifying in Australia.
"Bottas said he was free of pain by the end of last week and that the team had changed his seating and pedal position to ensure his 'back is in a more neutral position' to prevent it happening again. He said the pain started when he braked for Turn 13 in the second part of qualifying and 'it was like a knife in my back'.
"He was prevented from racing by FIA doctors despite passing the extrication test, a decision he said was 'disappointing' but one that he 'understood and respected'."
Fernando Alonso claimed his first F1 pole and podium at the Sepang circuit in 2003. He has won the race on three occasions and with three different teams (Renault, McLaren and Ferrari)
And another first for 2015 - Fernando Alonso makes his first appearance in the McLaren at a grand prix weekend.
Out rolls the Manor Marussia for the first time in 2015 with British driver Will Stevens the first to venture on to the circuit for the team.