Nico Rosberg keeping expectations in check despite strong Canadian GP

Schumacher delivered the best form since his Formula 1 comeback when he fought hard for a podium finish in Montreal, before eventually finishing fourth after being unable to defend from rivals in the DRS zones.

But although that result was the best of Mercedes GP's season so far, Rosberg says it is important the team realises it needs to do much better in lifting the performance of its car.

"We should not over-estimate the performance in Montreal," explained Rosberg. "In qualifying we were sixth and eighth, and that is the level of performance we have at the moment.

"With a good race we can do a little bit better than that, but it is not realistic to think that on pure performance we are able to go on the podium at the moment."

Rosberg spent time at the team's Brackley factory last week to get a better understanding of the situation the team is in this year, as he remained confident it would get on top of things.

"I wanted to get up-to-date with developments and how the near future is doing - how much progress we expect to have," he said. "I also wanted to catch up with the engineers, review Montreal and things like that.

"I also spoke to Ross and the feeling was positive, for sure. It is still as always that this team will have success. It is just a matter of time, although it is hard to say when. Obviously we are not where we want to be."

When asked what the team was lacking to achieve that success, Rosberg said: "Just general performance from the car. The car in general is not there yet, where it needs to be to win races."