Mercedes' advantage over its 2014 rivals might be bigger than is currently thought.
Nico Rosberg won the Melbourne race with a half-minute advantage, but Ferrari's Fernando Alonso was quoted afterwards by Auto Motor und Sport as suspecting the German was "playing with us" on the roads around Albert Park.
"Probably they have some more tricks up their sleeve, so we have a lot of work to do," he is quoted by Italy's Tuttosport.
And he thinks Williams has the edge on that group.
"I'm sure they did not give their best and that they are at least second best at the moment."
"90 per cent of the problems are associated with the software and how the ERS and the engine work together," Horner is quoted by Germany's Sport1.
"The break after Australia is just too short (to win in Malaysia)," he said.
Worse still for Mercedes' rivals is that the Brackley based team is not resting on its laurels.
The team took an updated front wing to Melbourne but decided not to use it.
"We only had two, and we didn't want to risk damaging one and then running one car with the new wing and one with the old wing," said Mercedes designer Aldo Costa.
The other issue is that the new, radically-short nose that goes with the new wing design reportedly failed the mandatory FIA crash test.
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