F1 Malaysian Grand Prix 2015: Lewis Hamilton overcomes early engine woes to set fastest time as Kimi Raikkonen beats Nico Rosberg

Rosberg could only manage third with Red Bull rookie Daniil Kvyat an impressive fourth

Hamilton's Mercedes is winched onto a recovery lorry (Getty Images)

Lewis Hamilton hailed his crew of mechanics following a difficult day at the office that he claims left him "heavily compromised" ahead of this weekend's Malaysian Grand Prix.

Fresh from an Australian Grand Prix 'triple crown' of pole position, fastest lap and race win, Hamilton was forced to pull his Mercedes to one side after just four installation laps in the first practice session at the Sepang International Circuit.

After the car was hauled back to the garage there were initial fears an engine change may be required, only for the fault to lie within the power unit inlet system.

The depth of the issue within the system, however, meant Hamilton did not return to the track until 38 minutes into the 90 of FP2.

But the 30-year-old wasted no time in getting up to speed as he went on to set the fastest lap, being the only driver to dip under 100 seconds with a time of one minute 39.790secs.

"It was an amazing job done by my guys to rebuild the car, get the engine and gearbox back on and to get back out," said Hamilton.

"I am very grateful for that. Especially here where it is so hot and so difficult for the tyres, so it was really important get back out."

Lewis Hamilton was forced to end his first run after just four laps (Getty Images)

Losing too much time, however, may yet prove costly as Hamilton added: "It affects you quite a bit.

"Fortunately I got a few laps in with a longer run at the end, but in terms of my set-up, I have not made any changes and it is quite a bit off from where we need it.

"Overall, my preparations have been heavily compromised. Whenever you lose a session, and most of the second session too, that definitely doesn't help.

"In the end, just to get some laps was crucial. If I had missed all of today then Sunday would be hard.

"Right now I have some improvements to make to the balance and the settings, so I am sure we will tweak and improve it because we have not got the car dialled in."

Lewis Hamilton returned to the track to set the fastest time of the day (Getty Images)

Ferrari's Kimi Raikkonen was second quickest in both sessions, the Finn finishing 0.373secs adrift of Hamilton's team-mate Nico Rosberg in FP1, and remarkably exactly the same time off the Briton in FP2.

Although Ferrari are showing signs of closing in on Mercedes, Raikkonen said: "The car is still not perfect, but I'm sure we can improve for tomorrow.

"We have some work to do on the set up to make everything easier, but we'll do our best and we'll see where we end up in qualifying."

Rosberg had to settle for third best, just over four tenths of a second behind Hamilton, followed by Red Bull's Daniil Kvyat and Williams duo Valtteri Bottas and Felipe Massa.

Kimi Raikkonen managed to finish both sessions in second (Getty Images)

As for ailing McLaren, the returning Fernando Alonso was down in 16th, 2.7secs off the pace, closely followed by team-mate Jenson Button.

Alonso, who sat out the first race Down Under as he recovered from concussion suffered in a crash in testing, claims McLaren have progressed from where they were a fortnight ago in Melbourne.

Nico Rosberg topped first practice but could only manage third in second practice (Getty Images)

The double world champion said: "It felt great in the car.

"After the gym, the simulator, whatever you do it is not the same as the car, so I enjoyed so much driving here.

"It was really the second day of testing for me because I had one good day in Barcelona with 63 laps and then today with 45 laps.

"And the car was much better than expected. The experience we had in winter we had a lot of problems after four or five laps.

Fernando Alonso returned to action following his recent concussion (Getty Images)

"But today we ran 45 laps with zero problems, everything went as we predicted.

"We will see in qualifying where we are, but I think we were 4.6 seconds behind pole position in Australia.

"Here, maybe we could be 3.5 seconds down, so that is a one second or 1.5 second gain in two weeks, so a big step forward."

Roberto Merhi's first ever run in the Manor Marussia ended in the gravel trap (Getty Images)

Manor also hit the track for the first time this season after months of uncertainty and missing Australia due to technical issues despite being present at the Albert Park circuit.

Rookie duo Will Stevens and Roberto Merhi completed 34 laps between them, with the Briton 5.9secs down and the Spaniard 7.4secs adrift, with the latter's day cut short by a spin into the gravel.

PA