Sepang - Mercedes totally dominated the F1 season-opener but are taking nothing for granted at the second stop in Malaysia where Fernando Alonso and Valtteri Bottas return to action after passing fitness tests, and the Manor Marussia team is set for a 2015 debut as well.
Also read: Alonso set to race in Malaysia - Mclaren
World champion Lewis Hamilton and his Mercedes teammate Nico Rosberg are the top favourites for Sunday's Malaysian Grand Prix but are keeping their feet on the ground despite an overwhelming win in the season-opener.
Hamilton handily dominated in Australia ahead of Rosberg, with third-placed Sebastian Vettel of Ferrari a massive 34 seconds behind.
The gap has led to fears that Mercedes will dominate even more than in 2014 but the team is having none of it ahead of the demanding race in sweltering conditions.
"Australia was a great way to start. To pick up where we left off last year was awesome, Hamilton said.
"But if 2014 showed anything, it's that putting together a whole season is never easy. Winning the first race is just one small step in a long journey and I'm not reading anything into it."
The Briton has an early advantage over his German teammate and will aim to stay ahead by repeating his 2014 win in Sepang, while Rosberg aims to bounce back immediately as he hopes to beat Hamilton for the 2015 title.
"It's up to me to find that little bit extra. It's all set up to be another great battle between us this year and I'm ready for the fight," Rosberg said.
He added that "hopefully we will also have some other competitors pushing us as hard as we push each other, as this would be great for the sport."
But no one seems to be able, at least in this early stage, to challenge Mercedes - even though Mercedes motorsport boss Toto Wolff said that "Ferrari have made a clear step forwards (and) Williams also look very strong."
Ferrari were happy that their new man Vettel made the Melbourne podium, but the four-time world champion is well aware of the big gap, despite some general optimism.
"We must confirm our performance in the coming races and then, one step at a time, let's hope we can begin to close on the Mercedes. The gap is still big, but of all the teams, I think ours is the one that has improved the most over the winter," Vettel said.
Williams had Felipe Massa place fourth in Australia and now have Valtteri Bottas back as well after the Finn suffered a back injury in Melbourne qualifying and could not race.
Also cleared to compete again by F1 doctors is former champion Fernando Alonso who missed the Australian weekend over concussion he sustained in a pre-season training crash last month in Barcelona.
There was confusion about the cause of the accident. Alonso on Thursday spoke of a locked steering but said he had "zero concerns" getting into the car in Sepang.
Also to make the season debut is the reformed Manor Marussia team after the financially troubled outfit was unable to drive in Melbourne.
"After the disappointment of not meeting our objectives in Australia, we head to Malaysia this week hoping for a more typical race weekend," team principal John Booth said.
The Melbourne race saw only 15 cars start and 11 finish but Sunday's race on the 5.543-kilometres course is set for the full registered field of 20 cars.