Ducati's Valentino Rossi is continuing to struggle with corner exit speed at the Le Mans MotoGP round, losing vital time which saw him slip down the free practice timesheet to end up behind Hector Barbera.

The Doctor managed to stay one place ahead of team-mate Nicky Hayden but the pair are a fraction under 1.3s slower than leader Casey Stoner but only half a second slower than Cal Crutchlow.

The Italian says he intends to concentrate on working out a strategy to improve grip on a worn tyre which will be vital at the end of Sunday's race, should it remain dry.

“This afternoon we tried some bike settings that were quite varied, and we’re trying to understand what the right direction is for finding more grip on corner exits. So far, particularly when the tyre starts to wear, we’re losing a lot compared to the others," said Rossi.

"Our gap to the front is pretty large, and although the gaps in our group are quite small, there’s more time between us and seventh place than there was in Portugal. We’ll have to try to do better. We’re trying some different things and we’re working hard, so we’ll see how we do tomorrow.”