Former Ferrari driver Gerhard Berger says Lewis Hamilton has the edge over his Mercedes team mate Nico Rosberg at the midway point of the 2015 season - but only if he stays 'perfect'.
The Austrian, who competed in 210 Grand Prix races for teams including Arrows, Benetton and McLaren between 1984 and 1997, made his comments about the current state of the sport this week in an interview with German-language site f1-insider.com.
"Lewis has a small advantage, but not enough to even allow the smallest error," he said. "Nico didn't drive a good race in Hungary, but overall he seems to have caught up again compared to the weak start he had to the season.
"You saw that especially in Austria. He won on his own and not just because Lewis screwed something up.
"But if Lewis goes perfectly, he will come out on top. If not, Nico turns the duel in his favour."
Berger credited Mercedes for putting both men firmly at the front of the field, and said it was due to their having spent the time and money to perfect their power plant for 2015. Other teams have struggled to achieve equal footing in either raw speed or reliability in the first half of the current season.
"Mercedes was - unlike Renault - willing to spend the necessary budget," he pointed out. "In addition, they have not rested on their engine, but also built a very, very good car. And with Lewis Hamilton and Nico Rosberg they have two absolute top drivers."
But Berger was optimistic that his old race team Ferrari would prove to be a big factor in the second half of the year.
"Ferrari has given the right answer in Hungary and made a much bigger step than I or others would have expected.
"This also applies to the new team manager Maurizio Arrivabene, who has done a much better job than anyone would have thought.
"Sure, there is still a long way to Mercedes, but you have to remember where they started from."
Berger also added that he felt Kimi Raikkonen was looking increasingly likely to stay at Ferrari in 2016 alongside Sebastian Vettel, as possible contenders to take the Finn's race seat next year all look to be stymied by pre-existing contracts with other teams.
"It depends on when there is an ideal opportunity which is perhaps not there yet," agreed Berger. "This is Ferrari's decision. Eventually, they'll have to replace him with someone younger.
"Sebastian is one step ahead, but what makes Kimi so likeable: he is not a politician, but tries to deliver in his car as best as possible. Both together make for a good driver combination."
Red Bull motorsport director Dr Helmet Marko recently dismissed speculation that Max Verstappen might be bound for Maranello in place on Raikkonen next season.
"I find that very interesting. However, I also know that Max has a long-term contract with Red Bull, which also includes 2017," he said.
Click here to find out the budgets available to each F1 team during the 2015 season
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