By Alan Baldwin
SOCHI, Russia (Reuters) - Formula One champions Mercedes have yet to be beaten in Russia, which hosts a grand prix for the fifth time this weekend, but Ferrari's Sebastian Vettel still sees nothing to fear in Sochi.
The German is 40 points adrift of Mercedes rival Lewis Hamilton with six races remaining and is running out of time to reassert himself in the battle of the four times world champions.
Hamilton has plenty of momentum and has won twice in Russia, even if last year it was Finnish team mate Valtteri Bottas who came out on top in a race run in late April rather than at the sharp end of the season.
Bottas, 110 points behind the Briton in the championship, may this year be required to play a 'wingman' role which would leave Vettel facing a fully focused foe in Hamilton, who has won four of the last five races.
Vettel did his best to stay positive after finishing third last time out in Singapore -- a round Ferrari were expected to win.
"Russia, I think, has been getting better the last years for us, so it should suit our car as well," the German told reporters.
"I don’t think we have any tracks to fear that are coming," he added.
"I think our car is working pretty much everywhere and that’s a strength of our car, so no need to be afraid of what’s coming."
Hamilton, who has been keeping the paparazzi busy since Singapore after being spotted holidaying in Dubai with rap queen Nicki Minaj, knows that he can deliver another hammer blow to his rival.
An eighth win of the season on Sunday would mean he can finish runner-up in every remaining race and still be champion, even if Vettel wins all five.
He and Mercedes also know how fast things can change, though, and will be taking nothing for granted.
"There are no easy wins this season. We have to fight hard for every bit of performance in order to have a chance to fight for victories," said team boss Toto Wolff.
"We have a good track record in Sochi but we know that Ferrari and Red Bull will give it everything to break our winning streak, so we must fight as hard as ever to make sure we bring home as many points as possible.
"There are six races remaining and plenty of points to score, so it doesn't give us any comfort," added the Austrian.
"We will continue to concentrate on every single session, trying to optimise the car in every possible area - and we will go for the race win."
Red Bull's Max Verstappen will have something to celebrate regardless of the outcome as the Dutch youngster turns 21 on Sunday.
Saturday will be his last opportunity to become the first 20-year-old to secure pole position but that will be impossible if, as expected, he collects a raft of engine penalties.
The Force India pairing of Frenchman Esteban Ocon and Mexican Sergio Perez will be on best behaviour after colliding in Singapore, costing the team what looked like being a hefty points haul.
Local fans will also have one of their own to cheer on, although Sergey Sirotkin is likely to be some way off the pace on his home race debut for struggling Williams.
(Reporting by Alan Baldwin, editing by Nick Mulvenney)