Ross Brawn, Ferrari's tactical mastermind, says even he is amazed by Michael Schumacher's extraordinary form this season.

"Michael's been really astonishing this year," he said at the Canadian Grand Prix, where the world champion made history on Sunday as the first driver to win the same race seven times.

"Rubens (Barrichello) is doing a great job, but he is in Michael's shadow this year. Michael's unbelievable."

Schumacher has won seven of the season's eight races and Brawn saw little reason why he should not win most of the remaining 10 to come as well.

Asked whether any team could mount a sustained challenge to the champions, Brawn as ever refused to take anything for granted while hinting heavily that it would be hard.

"It's a very difficult thing to predict," he said. "We never like to say 'no' because you can just get caught out. It would be foolish of us to say no.

"What we are most pleased with is our consistency.

"(But) I'm sure there will be days when BAR, Renault, or maybe the new McLaren and Williams, will give us a very hard time."

Ferrari have been constructors' champions for the past five years while Schumacher has won the last four drivers' titles and is on course for a record seventh.

But Brawn said he did not know how long the Italian team could keep up such a level of performance.

"Somebody may come along and blow us away and we don't have the strength to respond, or we may take a direction which is wrong and have to come back, but we will always be there or thereabouts," he said.

"The group of people we have at Ferrari will always be competitive in some form or other, but whether we can continue the level of performance we have now I don't know.

"We don't set out to dominate. We just set out to be competitive and as long as we can do that, which we have always been in the last eight years, then we'd be happy with that.

"The current situation is a reflection on not only the job we are doing, but also the other teams. It's a bit unusual and I don't see that going on indefinitely."

Schumacher, now with 77 wins to his name, has been with Brawn since they were at Benetton together in the early 1990s and the pair have a close bond.

"The good thing about us is that we are a team and we discuss things together and we decide things together amongst ourselves," said the German after his victory.

"The main responsibility in this case is down to Ross because he is the master of strategy, and whenever we are not sure then he will call the shots.