Berger happy with Speed, Liuzzi

Berger said before the start of the season that Speed needed to show more commitment, as the American's renewal deal was delayed nearly until the first race.

The Austrian, however, says Toro Rosso have been pleased with their drivers' showing, and he highlighted Speed's Monaco Grand Prix, where the American finished in ninth position.

Berger also denied the team were considering changing their line-up this year.

"We are not changing drivers," Berger was quoted as saying by Autosprint. "In the last race both Speed and Liuzzi did an excellent job. We were fast in any condition, including in the rain on Saturday morning.

"Monaco was a success, Scott drove very quick in the race and what happened to Tonio wasn't his fault. We managed to get a ninth place and, what matters most, we did it with our own strengths. But we must work in the same way in Canada as well already."

Berger believes that if the team can perform consistently like in Monte Carlo, they could score their first points of the season.

"If we manage to stabilize the performance level we had in Monaco, then we can always stay close to the top four teams and, in the end, take a few points if one of the cars ahead retires," he said.

"That's the maximum we can do, but I don't want to hear about results depending on the track."