BARCELONA • Ferrari are hoping to take strength from their pace in pre-season testing, as they seek to dash Mercedes' bid for a fifth successive one-two finish in tomorrow's Spanish Grand Prix.

Four-time Formula One world champion Sebastian Vettel warned that there was no silver bullet, but recovering the sort of speed the team showed in March would be a step in the right direction.

"Obviously, the car was really good in testing. But 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 we know 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've never found the silver bullet."

Ferrari dominated pre-season testing at the Circuit de Catalunya, but Mercedes have won every race since then in a one-two formation.

Valtteri Bottas, the championship leader a point clear of teammate Lewis Hamilton (86), is 35 ahead of Vettel, while Ferrari are 74 behind the champions (173).

Yesterday, the Finn set the early pace for Mercedes in the first practice for the Spanish Grand Prix with a best lap of 1min 17.951sec on soft tyres.

Ferrari's Sebastian Vettel (1:18.066) was second, with Charles Leclerc (1:18.172) close behind and Hamilton fourth.

Bottas missed the last half-hour due to an oil leak that shut down the car and had to be investigated.

When asked of his rivalry with Bottas, Hamilton said: "We have an agreed rule set out so that we try to finish the races one-two and we play supporting roles either way."

AGENCE FRANCE-PRESSE, REUTERS

F1 SPANISH GRAND PRIX

Practice 3 & qualifying: Singtel TV Ch114 & StarHub Ch208, 5.55pm & 8.30pm