Mercedes F1 team wary of Red Bull threat after Australia resurgence

Although the German car manufacturer is the team to beat at the moment, its chiefs were surprised at the way in which Red Bull emerged from a troubled winter to become its closest challenger in Australia.

Toto Wolff, the Mercedes motorsport boss, reckons that the swiftness of Red Bull's return must act as a warning for his team to keep pushing hard.

"If you could see where they [Red Bull] were two weeks ago in Bahrain, we need to be very careful," he said.

"We haven't seen Sebastian [Vettel] running with a reliable car and a fast car and you would expect him with his experience to go even faster.

"We have to keep on pushing."

Although reliability is Mercedes' biggest concern at the moment, following Lewis Hamilton's retirement in Australia, Wolff reckons that the team cannot ignore pushing on with more car improvements as well.

"We have to continue working on reliability but equally drive performance," he said.

"You need to add downforce to the car. You need to make all the systems work with each other.

"You need to improve on cooling, and you need to improve the whole packaging of the car."

Wolff reckons it would be a failure if his outfit did not capitalise on the performance advantage it currently enjoys over its rivals.

"I don't see it as a big advantage to be honest," he said of the team's performance advantage, "because you have a DNF and you lose points.

"McLaren is leading the constructors', so we cannot pause.

"We have a little bit of a margin at the moment, and losing that margin is something which I would consider as a failure."