Sebastian Vettel led the pace during the first day of pre-season testing in Jerez. The German who has switched from Red Bull was followed by another Ferrari powered car the Sauber of Marcus Ericson and Mercedes Nico Rosberg.
But the Mercedes car looked strong as the team looks to successfully defend both the drivers and constructors championship. It was a difficult day for McLaren who only managed six laps as they renewed their engine partnership with Honda. Alonso was 18 seconds off the pace as the team struggled to get the car and engine running together.
However, Ferrari was strong this time last year but slipped away by the time the season had begun. Mercedes did show they can challenge the Ferrari by closing the gap to under a second. Daniel Ricciardo was fourth but chief technical officer Adrian Newey said he did not expect the team to be able to challenge Mercedes for the championship this season.
Elsewhere Williams Valtteri Bottas was fifth fastest, completing the second highest number of laps in his Mercedes-powered car. While Rookie Carlos Sainz Jr was the fastest Spaniard ahead of Fernando Alonso
Fastest lap times, day one of first pre-season test in Jerez
1 Sebastian Vettel (Ger) Ferrari 1:22.620
2 Marcus Ericsson (Swe) Sauber-Ferrari 1:22.777
3 Nico Rosberg (Ger) Mercedes 1:23.106
4 Daniel Ricciardo (Aus) Red Bull-Renault 1:23.338
5 Valtteri Bottas (Fin) Williams-Mercedes 1:23.906
6 Carlos Sainz Jr (Spa) Toro Rosso-Renault 1:25.327
7 Fernando Alonso (Spa) McLaren-Honda 1:40.738