Lewis Hamilton believes Ferrari's straightline speed will make them hard to beat at this weekend's Canadian Grand Prix.
The Briton arrives in Montreal, scene of his maiden grand prix win last year, in the championship lead after winning in Monte Carlo.
Ferrari, however, were very strong on the streets of the principality, where they struggled to match McLaren last season.
They also failed to match their rivals in Canada, but the Italian squad are adamant they will also be fast in Montreal.
Hamilton reckons Ferrari's top speed could give the Maranello team the edge.
"I think it is difficult to say," said Hamilton when asked to compare this year's McLaren with last season's car. "Last year I think we had a very good car. Obviously with the driving aids we had, I think the package was stronger in some areas than the ones we have right now.
"But that is because we have had some aids taken away. But we should be slightly better over the kerbs, which is definitely suited for this sort of circuit. And we've improved the engine and improved the aero, so we should be quicker overall. </p>
"It is going to be interesting to see who is quick tomorrow. The car with the quickest car down the main straight, you know who they usually are, so it will be difficult to beat them (Ferrari). But I still feel quite optimistic and feel that we can make quite a big difference here."
Thanks to his win in Monaco, Hamilton stopped a three-race winning streak from Ferrari, and he reckons his team's morale was boosted by it.
He claims, however, that it didn't change much for him.
"I don't think it really made much difference to be honest," he said. "We had had a couple of strong races. But I think mainly for the team, not for me, it was a big confidence boost.
"They have been working so hard and they deserved it more than anyone I think. For me, though, I didn't particularly need a confidence boost.
"I had had a couple of strong races before, so for sure it was nice to have a win - but I am not going to get overly excited about it."
The McLaren driver admitted he was not too surprised to see Ferrari fighting on top at Monaco, despite their problems in previous years.
"I don't really think they made any progress. I think they have been quick all year and I don't think they particularly made a step compared to the previous race. But their car is better this year than last, so it was to be expected."