Casey StonerCasey Stoner was downbeat about his prospects of victory at Brno this weekend, despite having finished on the podium in the last four MotoGP races.

The Ducati rider was third at Assen, Barcelona and the Sachsenring, and second to Jorge Lorenzo last time out at Laguna Seca, but he does not believe the string of good results put him in a position to challenge the Spaniard for victories.

"The results might look like they're getting better, but we've been hitting the maximum too early and we can't seem to improve as the weekend goes on," Stoner said. "We really need to step it up, and I've been trying week in week out to find some solution to be more competitive. But when I find something that I think is going to work, when I'm trying to gain on them is when I'm making mistakes.

"I need to find a setting I'm a little bit more comfortable riding. A couple of tenths could be crucial and maybe we can put up a fight, but if things keep going like they have been it's going to be very difficult. But everyone at Ducati is working very hard and we're going to see what we can do in this last part of the season."

Stoner is currently fourth in the championship, 12 points behind Honda's Andrea Dovizioso and 13 ahead of the recovering Valentino Rossi.