Red Bull chief Christian Horner has warned his team not to expect an easy run in this weekend's Malaysian Grand Prix and to be ready for a backlash from big rivals Ferrari and McLaren.
Red Bull's world champion driver German Sebastian Vettel won the season-opening Australian Grand Prix convincingly two weeks ago, leaving the chasing pack in his wake.
But Horner believes that race was not an indicator of what lies ahead and said he expects to see Ferrari's Spanish two-time champion Fernando Alonso and McLaren's British former champions Jenson Button and Lewis Hamilton back to their best.
"Anyone who thinks otherwise would be making a mistake," said Horner.
"These other guys don't want to be left behind and they will push hard to be as competitive as possible. We are in for some very tough and competitive races."
Red Bull won both the drivers and constructors championships last season and started their 2011 campaign in style with Vettel triumphant at Albert Park and his disappointed team-mate Australian Mark Webber finishing in fifth place.
"Mark was not happy with that but we have found a few pointers about things with the car and I expect him to be back up the front," said Horner.
Hamilton, too, believes he has a chance to win another title this year and was hugely encouraged by the performance improvement in his McLaren car in Australia, where it ran with a revised exhaust layout, floor and rear wing configuration.
"I feel we are right back in it, on the pace and capable of competing this year," said Hamilton, 26. "We are back at it and it feels great."
Button said he also felt encouraged by his car's performance but warned that in a long season anything may happen and, agreeing with Horner, suggested that the contest may well unfold like a long arms war with the teams working on revisions all season long.
"It will be another very close fight and I think it could go all the way down to the wire again," he said.
In a race of four or more pit-stops, according to new tyre suppliers Pirelli, the weather and an ability to conserve tyres could prove decisive. It is expected to be sweltering with high humidity.
"It is always important to be properly hydrated at Sepang," said Button.
While he did that, Ferrari were working overtime in analysing the statistics that followed Alonso's drive to fourth place in Australia, a disappointing result after the team had set the pre-season pace.
They have concentrated their efforts on improving their qualifying performance.
And Germany's seven-time champion Michael Schumacher, 42, made clear he intends to push hard this weekend for a good result after such a disappointing start for the Mercedes team in Melbourne.
Both he and compatriot and team-mate Nico Rosberg failed to finish.
"Don't write us off, it is much too soon for that," said Schumacher.
His team chief Ross Brawn said: "It was a bad start but we have been doing a lot of homework and I am sure we will be more competitive this time. Now is a test of the strength and resolve of the whole team."