DOHA (AFP) Australias Casey Stoner set the fastest time in practice for the season-opening Qatar Grand Prix which will be staged under floodlights on Sunday. The Ducati rider, who is seeking his fourth successive win at the Losail track, clocked 1min 55.500sec, just over half a second ahead of the rest of the 17-strong field late Friday. Stoner was the only rider under the 1min 56sec barrier. Everything started off very well; we got a quite good feeling with the bike early on, he said. When we changed the setting I actually did not prefer the feeling of it, but the lap time was better. Now were trying to get a bit more balance in the bike to get a little better understanding of it, and still be able to do those lap times, said the 24 year-old. Stoner warned that there would be further work ahead of Sundays season-opening race. Were quite happy with where we are at the moment but I believe everybody will catch up over the weekend, so we definitely need to stay on top of our game and try and improve our set-up a little more. Spains Jorge Lorenzo, on a Yamaha, who admitted prior to the weekend that he may not be at full fitness as he continues to recover from a hand injury, set the second best time of the hour-long session with 1min 56.026sec. His team-mate and reigning world champion Valentino Rossi, was third on the timesheet on board his factory M1 prototype. The Italian, who will aim to get his title defence off to a winning start, timed in at just two-thousandths of a second off Lorenzo. Lorenzo said he had been quite happy with his hand. I tried riding for the first time without the extra hand protection and I was okay, said the Spaniard. I felt good on the bike and my thumb didnt really hurt, it was a lot better than at the test. Rossi said he had expected to be faster. The lap time is not bad but it could be better, said the 31-year-old. The conditions are much better than during the test, its warmer and a lot less humid so Im happy about that. But we dont have enough grip and I was sliding quite a lot so we need to try to find a way to improve this. Stoner is always very fast here and I hope we can close the gap to him by making some small changes to our suspension. If we can stop the bike sliding then we will be a lot faster.