Sebastian Vettel says Ferrari must seize any opportunity to upset Mercedes, while also acknowledging the defending champions remain the benchmark as F1 enters the European leg of its season in Spain next weekend.

The four-time world champion is currently third in the Drivers’ standings, 28 points adrift of leader Lewis Hamilton but merely one behind his Mercedes team-mate Nico Rosberg.

What’s more, Vettel is the only racer who’s beaten the reigning world champion in a straight fight this year. The 27-year-old’s victory in Malaysia could even be seen as Mercedes’ sole genuine defeat since the new hybrid turbocharged power units were introduced last season.

After a dismal 2014 campaign that saw Ferrari fail to win a race for the first time since 1993, the Scuderia has bounced back spectacularly to leapfrog both Red Bull and Williams in this year’s pecking order.

Having joined Maranello from Milton Keynes over the winter, Vettel also looks rejuvenated and poised to take the fight to last year’s victors but admits they still have the edge in front.

“We are trying to (challenge) Mercedes, and we must be right behind them and pounce if something goes wrong with them,” Vettel told German news agency dpa. “But it is also important that we are not passed by other teams.

“Mercedes still has the strongest package. You don't make up such a deficit quickly. Ferrari has taken a step forward in winter but it will take a while to be on the same level as Mercedes.”

Next weekend’s Spanish Grand Prix will give Vettel another opportunity to match Ayrton Senna’s tally of 41 grand prix wins, although the German has only triumphed once at Circuit de Barcelona-Catalunya (in 2011 with Red Bull).

Click here for a look at the radical Honda power unit design

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