Sebastian Vettel, a four-times Formula One world champion with Red Bull, warned there was no silver bullet but recovering the sort of speed they showed in March would be a step in the right direction.
"Obviously, the car was really good in testing. We arrived in Australia and we struggled a little bit to feel the same," the German told reporters on Thursday.
"I think the first four races for us have been a little bit up-and-down. There were stretches where the cars felt really good and other parts where the car hasn’t -- but deep down we know that the car is strong.
"So, we are trying to put the bits together and trying to understand. We haven’t found the silver bullet – but in the last 10 years I never found the silver bullet so I don’t think it exists."
Ferrari dominated pre-season testing at the Circuit de Catalunya but Mercedes have won every race since then in one-two formation.
Valtteri Bottas, the championship leader a point clear of Hamilton, is 35 ahead of Vettel while Ferrari are 74 behind the champions.
Vettel, as did Hamilton, said the reality was far closer than the numbers suggested and it just came down to getting the details right.
"Now, this weekend will be interesting for us because obviously we had such a good feeling and it’s not so long ago," said the German.
"I’m pretty sure I remember how the car felt and it will be interesting to see how it behaves in the next couple of days. But I’m quite confident if we can get to that level then we should be very competitive."
Ferrari have brought forward by two races an engine upgrade to give them the best chance of getting back in front of Mercedes at the circuit outside Barcelona.
Hamilton has won there for the past two years and three times in total.
(Reporting by Alan Baldwin, editing by Ed Osmond)
