Hamilton says Mercedes have "real big problems" to resolve

SEPANG, Malaysia (Reuters) - Formula One world champions Mercedes have some "real big problems" to fix with their car, title favourite Lewis Hamilton said on Sunday after finishing second in the Malaysian Grand Prix.

The Briton, now 34 points clear of Ferrari's Sebastian Vettel and well on his way to a fourth title, started in pole position but lost out to Red Bull's 20-year-old Dutch driver Max Verstappen.

Hamilton was helped by an engine problem sidelining Vettel in qualifying and another issue preventing the German's team mate Kimi Raikkonen from taking his place on the front row of the starting grid.

But Verstappen was significantly faster once the race started while Vettel showed the Ferrari's potential by going from last to fourth and beating Hamilton's team mate Valtteri Bottas.

"There is (a fair amount of work still to do) but there's nothing we can do," Hamilton, who was also gifted a win in Singapore two weeks ago when both Ferraris collided at the start, told Sky Sports television.

"It's the way the car is.

"I think globally we have not got the best car and we've done an exceptional job with what we have. There are some real big problems that I can't really explain to you...

"But we really need make sure we rectify them for next year's car if we're going to have any chance of fighting both these teams next year when they step up their game," added the Briton.

Hamilton said the car was good at some races, and not at others, but Mercedes would do everything they could to stay ahead.

Team boss Toto Wolff also sounded far from celebratory, despite Hamilton stretching his lead by six points with a hefty dose of luck.

"I am just very down, I must say," declared the Austrian.

"We have lost so much pace this weekend...how can a car that is so fast on many circuits lose so much with a tyre that is overheating?

"Probably if you look at the real pace today it would have been P5 (fifth). And that is worrisome. Now let's see what happens in Suzuka. We have a couple of days to try and understand."

The Japanese Grand Prix at Suzuka follows on immediately from Malaysia, with four races remaining after that.

(Writing by Alan Baldwin in London, editing by Toby Davis)