Stoner not yet comfortable with set-up

The world champion, aiming to fight back following a series of disappointing results, wound up third quickest in the afternoon session, when the track was at its wettest.

In the morning, with a damp track, he finished down in ninth place.

The Ducati rider admitted he had fun running in the wet, but said there is still work to do before he feels comfortable with his bike's set-up.

"This morning was half dry and half wet so it was pretty pointless going out on slick tyres and doing slow times," said Stoner. "That's why we decided not to use them at the end of the session, as a few other riders did.

"This afternoon we got some track time in fully wet conditions, which is much more useful. Having said that it was very wet and visibility was almost non-existent - especially behind the screen.

"It's hard enough trying to see through the screen without having rain splattered all over it and we don't exactly have windscreen wipers to get rid of the water. So it was quite hard visibility-wise but it was actually quite a lot of fun because the grip was good, especially at the beginning.

"We don't really feel as though we've got the setting down yet. I didn't really feel 100% comfortable on the bike - it was very nervous and I wasn't getting much feeling from the tyres so we definitely need to work a little bit harder tomorrow and try to find a different solution if it's going to be wet."

Teammate Marco Melandri was slowest in the afternoon after continuing with his problems to ride the GP8.

The Italian was 12 seconds off the pace after 11 laps, and said he felt he could hardly ride the bike.

"Today has been really difficult because we haven't been able to find a good setting with the engine braking - to the point that this morning on a damp track I ran straight twice because the wheel was locking," he said.

"In the afternoon the rain increased and the situation clearly got worse, so much so that I didn't feel I could ride. Tomorrow we need to find a solution so I hope it is dry."