Button returns to Williams cockpit

The Williams new-boy, who sat out recent tests due to back problems, was fourth quickest in the wet session, with Luciano Burti fastest.

The team also practiced pit-stops during Tuesday's session.

Button said: "Apart from the atrocious weather conditions, today went well.

"I have never simulated full pit-stops before and given how wet it was today, the pit-sop practice was a very valuable learning experience for me.

"As always, the team is doing a great job in developing my learning and should tomorrow allow us to run in the dry, the better it will be for everybody before the Australian Grand Prix."

Jaguar tester Burti recorded a fastest time of 1.40.54s after completing 23 laps.

Jordan's Jarno Trulli was second fastest (1.41.71s) after running 16 laps.

Third was Alex Wurz in the Benetton (19 laps - 1.42.17s).

Prost's Nick Heidfeld completed 10 untimed laps.

British American Racing, McLaren and Arrows are expected to run on Wednesday.

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