MotoGP World Championship leader Casey Stoner may have qualified in second for Sunday's US Grand Prix, just 0.072sec behind Jorge Lorenzo, but the Australian thinks both the Yamaha rider and his own Repsol Honda team-mate Dani Pedrosa are currently faster.

Stoner spent much of qualifying behind the Spaniards, before snatching second on his very final lap, but believes he's trailing them both in terms of race pace around the Laguna Seca circuit.

"For the whole session we were trying to find the right set up," said Stoner. "All weekend we've been struggling a little and we've not found anything I'm comfortable with, I've closed the front many times and we're still looking to find some balance on the bike to get it working on this track, where we expected it to work well.

"On my first soft tyre I encountered some traffic and was held up, also there was a crash and a yellow flag so I lost my chance on that tyre. Then on the next soft tyre we had one lap to find some pace and we managed front row which is important for tomorrow.

"I don't feel we're running with the pace of Dani and Jorge, they seem to be constantly one to two tenths quicker but we have warm-up tomorrow morning to find something in time for the race so we'll see what we can do".

Stoner starts round ten with a 15 point lead over world champion Lorenzo, who crashed heavily in morning practice.

Stoner has won four races this year, with Lorenzo and Pedrosa winning two each.