Heidfeld optimistic after Mugello test

The German completed 51 laps of the Italian track and spent the time honing his set-up for Indianapolis and working on future development for the Sauber team.

"Once again we had a very good test," said Heidfeld. "As far as the future is concerned we gathered a lot of useful information for next year's car while in the short-term our tyre testing for Bridgestone leaves me feeling optimistic for next week's US Grand Prix."

With a best lap of 1m23.21s, Heidfeld was just over half a second quicker than Brazilian Felipe Massa, who had his first Formula 1 run courtesy of the Hinwil-based squad on Tuesday and Wednesday.

While Heidfeld completed intricate suspension and damper work, team mate Kimi Raikkonen, who is switching to the McLaren team for next year, did not take part in the test as Sauber is loathe to give the young Finn any more insight into the development of next year's car than is necessary.