Ferrari driver Sebastian Vettel believes Mercedes' most powerful qualifying engine mode is still his rival's strongest weapon in this year's title fight.
After finishing a distant third in 2016, Ferrari has made a remarkable return to form this year and at the midway point of the season Vettel leads Mercedes driver Lewis Hamilton by one point in the standings. However, his advantage has been eroded by 24 points in the last two months as Mercedes has found form at a series of high-speed circuits and scored three victories and four pole positions from four races.
"It is probably true that at the last couple of races Mercedes have been stronger," Vettel said. "I think the real game changer is qualifying, they are able to turn up the engine between three and six tenths to us on the straights -- it was seven tenths in Austria -- so we need to be fair with that. It is something we can't do, we are working on it but it doesn't happen overnight.
"Saying that we need to give credit to the whole team, we must not forget where we have come from -- we have made the biggest step of all teams. Red Bull were very vocal in the winter about how good they would be this season and so far they haven't been there so everybody is pushing very hard."
Vettel says Ferrari is working hard to counter Mercedes' one-lap advantage but insists there is no need to panic.
"We are working on the advantage they have in qualifying and it is a no brainer, if you have the cars in front for the first lap or corner, the race looks different. We know where to tackle but it is not that easy.
"We have done a very good job so far this year, the car is great, it has been fantastic in the race [at Silverstone] -- arguably not quick enough -- but still quicker than what we have in terms of the [seventh place] result. There is no reason to panic or worry, they are very quick and they have a couple of advantages we need to work on and then it could be a different picture."
And Vettel believes the margins between winning and losing are still very small.
"I don't know. There are plenty of positives and for sure you always look after every race where you are. Silverstone wasn't good for us, full stop. We didn't get the result that we wanted, that we probably deserved, but that's how it is. We cope with that and we move on.
"You are always judged by the day. In Austria we missed the win by 0.6s, arguably Valtteri [Bottas] got very lucky with the jump start. That's how things go. If things go different, you come out as the winner and everything looks peachy. If you don't, like today, then everyone talks about huge disappointment and a disaster. But we are not here to lose. I hate losing, so we want to make sure we win next time."