Rosberg must 'save 2015 championship' - Ecclestone

Jul.4 (GMM) Sebastian Vettel says Mercedes is still clearly the favourite for British grand prix victory.

On Friday - as is increasingly the case in 2015 - Ferrari looked poised to pose a real challenge to the dominant champions this weekend at Silverstone.

Asked how much he can improve after practice, championship leader Lewis Hamilton said: "Hopefully a lot, because if not then we are in trouble."

But although, after Austria, Ferrari chief Maurizio Arrivabene ordered his cars to practice on Fridays with more representative fuel loads, Vettel says there is another reason for the misleading results.

"We know from Friday to Saturday that Mercedes turns the engine up," the German said. "It is not just Mercedes. If you look at Williams on Friday versus Sunday there is also a massive step."

And even on Friday, although Hamilton was outpaced by both Ferraris, the Briton's teammate Nico Rosberg maintained his recent grip on the top position.

Bernie Ecclestone hopes he can keep it up.

"It is up to Nico to save this championship," the F1 supremo told the Times newspaper. "We need him to keep things alive."

So maybe Ecclestone will be hoping Hamilton's 'rock star' lifestyle will help too, as many have been questioning whether the world champion's full focus is on F1.

"I get energy from all these things that I do. It doesn't take energy from me," Hamilton insisted, when asked about the criticism.

"My 20s went by really quick and I'm trying to make sure I do as much as I can, within my limits, in terms of energy and training and while performing. As long as I keep it balanced, why not?" he added.