Casey Stoner says Ducati urgently needs to address its issues with Bridgestone's qualifying-spec tyre, after he failed to get onto the front row at Le Mans.
Although the Australian was fastest for the part of qualifying when most riders were working on race set-ups, when everyone switched to softer rubber to fight for pole, Stoner failed to find any more time and saw his provisional pole become fourth on the grid.
"We have a lot of work to do to try and get more performance out of the softer tyre because our rivals seem to be able to make bigger improvements on it than us," said Stoner.
"We didn't manage to lap much faster than the times we were doing on the harder race tyre so that is a little disappointing because it would have been nice to start from the front row here but at the same time we know we have a good pace over race distance."
He remains confident about his chances in tomorrow's French Grand Prix.
"In general the bike is going really well, our race pace is more competitive than it was at this stage of the weekend in Jerez so I'm confident we can do a good job tomorrow," Stoner said.
By contrast, his team-mate Nicky Hayden reckons he will be hard-pressed to hold on to the fifth place he managed in qualifying.
"The second row for us is a positive result because to be honest my race pace hasn't been great and now we've given ourselves a chance because the start is so important here," said Hayden.
"We made a big step with the bike in the session this morning but weren't really able to follow it up with another one this afternoon so we have work to do tonight because at the moment it's looking like a really tough race for us."