Mercedes team chief Ross Brawn has forecast that his veteran seven-time champion driver Michael Schumacher will bounce back to form in this weekend's Spanish Grand Prix.

After a desultory showing at the Turkish Grand Prix where he finished 12th and was involved in a collision with Renault's Vitaly Petrov, the 42-year-old German talked of losing his joy - a comment that sparked speculation suggesting he was ready to retire.

But in this week's build-up to one of the key races of the season, Brawn made it clear he still had great faith in the driver he has backed and worked with successfully for most of the past 20 years.

"I am sure the last race wasn't very joyful, and that is what he was referring to. When you have a race like that, it's going to knock you back, but I think he's pretty resilient and I'm optimistic this weekend he will be back where we want him," said Brawn.

Asked about Schumacher's comments and the notion he was no longer enjoying racing in F1, Brawn said: "That is definitely taking it too far.

"I have spoken to him since then. We had a lot of technical discussions and he was hassling about what we were doing about the car, what is coming along, what improvements we have got - so nothing has changed. We are optimistic."

Schumacher has won the Spanish Grand Prix six times in his record total of 91 Grand Prix victories, the last in 2004 during his halcyon days at Ferrari, where he enjoyed unprecedented success and lifted five successive drivers' titles.

Brawn, one of the greatest pit-wall boffins of all time and a supreme designer and race engineer, was his technical boss throughout that period and also at Benetton in the mid-1990s when he lifted his first two championship crowns.

The Englishman said he felt the one-time champion may need to pay attention to a few details in his performance, but had not lost any of his raw competitive speed.

"It is just looking at the things that go wrong," he said. "They are quite small, and - although they were all significant in Turkey - until final qualifying, he was incredibly strong, but then he had some problems.

"So it is that last little bit that he needs to finish off. If he was slow from the beginning then you would be worried, but I am not worried because he is still very quick."

Schumacher's speed, motivation and performance will be one of the many issues being watched closely at the Circuit de Catalunya where after its 'blip' in China, the awesome champion Red Bull team hopes to maintain its general dominance this year.

Defending champion Sebastian Vettel said: "We know the Barcelona circuit well from testing - it should be suitable for our car and our plan is to get the best team result possible.

"Historically, Barcelona is a circuit that is poor for overtaking, but with the DRS this will now be quite different."

Vettel has won three of the four races so far this year, including the Turkish Grand Prix, and knows that a back-to-back 'double' of winning in Barcelona and then Monte Carlo, just seven days later, would give him a great advantage in his bid for a second title.

But he will be pushed hard by the pace of his teammate and rival Australian Mark Webber and former champions Lewis Hamilton and Jenson Button of McLaren as well as Ferrari's two-time champion Fernando Alonso, revelling in the support he receives at his home race.

Webber said: "For me, the circuit is great, the surface and layout are both very good for driving an F1 car on the limit. The last sector used to be very, very quick, but now, for the last few years, we've had a slow chicane which breaks the rhythm of the lap up a little bit. All in all, I enjoy driving the car on this track.

"Of course I want to improve on my result in Turkey. So that means trying to finish on the top step."

It could also be the last before technical rules' revisions are introduced, restricting the use of engine management systems, that could see some of the top teams' performances curtailed.

Champion Vettel leads this year's drivers standings with 93 points ahead of Hamilton on 59, Webber on 55 and Button on 46. Alonso is fifth with 41.