Michelin to look at Ralf's tyre problems

The German, who turned 26 on Saturday, lost the lead of the French race while he took an extended pit stop and was then plagued by tyre problems that slowed his car during his second stint.

"From that point his race was over," said Michelin motorsport director Pierre Dupasquier. "He might have caught Michael, but he would not have passed him. We don't know what the problem is, but I am sure it is a tyre problem if Ralf says it is.

"These drivers are extreme professionals and when they say something they are usually right. We don't know what the problem was, but we must find out. We haven't had the chance to analyse the data, but Ralf said that his car was difficult to drive on the second set of tyres - and we must get to the bottom of that."

Schumacher also had a problem with his tyres during the European Grand Prix at the Nurburgring after he dropped off the pace mid-race and the French firm has also experienced a drop-off in tyre performance dropping off in the middle section of race stints. However, Dupasquier insists it is not usually a problem between compounds.

"Previously we have had no problems with sets of tyres of the same compound behaving differently," he said. "During qualifying there was less than one-tenth of a second to choose between sets and that allowed us to take pole. Wear rates and pressures were identical on each set at the end of their race stints. Perhaps we should go back to the laps we did during free practice to see of we can get to the root of it."