Ducati Marlboro riders Casey Stoner and Nicky Hayden were left disappointed after a hard fought qualifying session.

Stoner dominated the opening stages of the qualifying but slipped back to fourth place with the time he set on his eighteenth lap, blaming setup problems for his performance in the last half of the session.

“I'm really disappointed with that session because I know we could and should have been fighting for pole position.” said the ex-world champion.

Stoner went on to say he started of the session well, but after switching tyres he suffered problems, “I had a much better feeling with the setting at the start of the session but midway through we went to change tyres and after that we suffered from a huge vibration in the bike. We still haven't worked out what it is yet so we need to figure it out and fix it for tomorrow.”

“I tried the softer compound but the chattering was even worse. I swapped to my other bike but we had a different setting in it that I hadn't tried and I didn't feel comfortable. Everything that could go wrong in the crucial second part of the session did go wrong but if we can fix this problem then we'll be in good shape for tomorrow. Anyway I'm happy with my pace in race conditions and I look forward to tomorrow.” he added.

Team-mate Nicky Hayden was relatively happy with his seventh spot on the grid but had hoped for more “I didn't actually make as big a step this afternoon as I had hoped from the morning session.” he said.

“On race tyres in the hotter temperature it was certainly tough and I was struggling a little bit. We had a couple of problems during the session but in the end I was able to find one good lap to get me into a respectable grid position, very close to the second row.”

Despite the happiness with his grid position the Ducati rider is worried about his race pace “I'm not too happy with my race pace – we're missing a few tenths and we have some work to do tonight to try and find where we can make them up.”

Hayden admitted he would of liked to be better off than seventh, but was glad that he wasn’t further down the grid.

“I'm never really happy with seventh place but to be honest today it was a pleasant surprise because it could have been much worse off than that if we were just a few tenths slower. We've got a big job to do tomorrow. 22 laps around here when your race pace isn't perfect is certainly not easy but that's what we train for. Hopefully we can improve in the warm-up, get a good start and we'll see what we got for them.”