Schu Jr gets Williams wake-up call

Schumacher has qualified poorly in the opening two grands prix of the season, but raced to points scoring finishes in both events, including a fourth place finish in Malaysia. He lies eighth in the world championship, however, while team-mate Juan Pablo Montoya is third.

Team principal Frank Williams and technical director Patrick Head are understood to have penned the letter, which says they feel that the German has not been driving to his full potential. Ralf went someway to answering his critics in testing in Barcelona last week when he topped the times on two of the four days.

Head, meanwhile, believes the team has made significant progress in recent weeks with its new FW25 chassis.

"What has really made a difference is a new front wing, which seems to work quite well," he said. "And for the first time we were running the new rear suspension that was always intended for the car, in place of the interim system we have had to use since the FW25 was launched. I think that Brazil should suit our car, and hopefully we will have a less bitty race than we had in Malaysia."