SOCHI, Russia (AP) — With the gap widening, Lewis Hamilton faces an increasingly tense Formula One title defense as his Mercedes teammate Nico Rosberg grows more confident by the race.
Heading into this weekend's Russian Grand Prix, the three-time world champion is already 36 points behind Rosberg - who is seeking a seventh straight win after winning the first three races of this season and the final three of last year.
While Rosberg has been faultless, Hamilton has struggled, colliding with Valtteri Bottas at the first corner in Bahrain, and finishing seventh at the last race in China following technical problems.
''It's a lot of points, a race and a bit, and I don't take it for granted that it is a big step,'' Hamilton said Thursday. ''I know I've got a lot of work to do ... It's a steep one to climb.''
But fueled by memories of his comeback to beat Rosberg in 2014, Hamilton has a strong resolve. That year, he was 29 points back but the British driver won six of the last seven races to clinch the title at the season-ending Abu Dhabi GP.
''On the flip side, in a shorter period of time, I've come from 29 (behind),'' the 31-year-old Hamilton said. ''There (are) 18 races (left), it's an average of two points per race, I believe, so it's not impossible.''
Hamilton has won both races in Russia to date, but last year's victory came after Rosberg retired from the lead with a broken accelerator pedal.
Despite leading the standings, and being in the best form of his career, Rosberg is cautious.
''I've been driving really well but my opposition had a really messy start, so that's the reality of it,'' he said. ''I definitely expect them all to bounce back, especially Lewis, and then it's going to be a great battle against him - as always.''
Perhaps in a bid to take the pressure off, Rosberg somewhat downplays his hot streak as ''just an awesome feeling'' - but the statistics show he is within touching distance of some famed names.
A seventh straight win would put him level with seven-time F1 champion Michael Schumacher and 1950s racer Alberto Ascari. The record is held by four-time champ Sebastian Vettel, who won nine races in succession on his way to the 2013 title with Red Bull.
As well of being wary of a Hamilton comeback, Rosberg highlighted the potential of Ferrari - despite a tough race in China, where Vettel and teammate Kimi Raikkonen collided.
''For sure they are a lot quicker than they have shown and we think they are very, very close to us,'' the 30-year-old Rosberg said.
Vettel, who is fourth in the standings and 42 points behind Rosberg, has a good ''gut feeling'' about his car.
''We are not sitting here waiting to have a lucky race,'' the German driver said. ''We are working very hard and we want to make progress.''
After a wild race in China packed with overtaking, Russia should be quieter. At a Sochi circuit which is traditionally low on tire degradation, strategic options are limited by tire supplier Pirelli's decision not to bring its new ultra-soft compound of tire.
Meanwhile, there was an air of resignation among drivers over planned rule changes for 2017, which seem likely to pass despite driver criticism that more downforce could make it harder to drive behind other cars - thus meaning fewer chances to overtake in a sport already struggling to provide excitement for its fans.
''I do want to be careful with what I say, but it's not great,'' Hamilton said.
Rosberg, although praising the sport's governing body, the FIA, for increasing talks with drivers, is also downbeat about 2017.
''Now all we can do is accept it, make the most of it, and hope there's some surprises,'' he said.
In a push to give drivers more protection, Red Bull said that Daniel Ricciardo will trial a new ''aeroscreen'' concept in Friday's first practice session. The device gives the driver a small reinforced windscreen designed to protect from flying debris.
The Red Bull device is the main rival to a metal ''halo'' which Raikkonen and Vettel tried out in pre-season testing in Spain to mixed reviews - with Hamilton calling it the ''worst looking'' modification in the sport's history.