The session began wet, and it took a while for the Indiana sunshine to burn off the surface water. M Schumacher didn't make it that far, however, as his Ferrari was stranded out at Turn 9 on its installation lap after some sort of electrical or hydraulic failure.

Friday pacesetter Trulli kept up his record of topping every session so far, but this time the Williams-BMWs ran him close. Trulli's 1m12.408s was just 0.060s quicker than Ralf Schumacher, while Juan Pablo Montoya was another couple of hundredths shy of his team-mate. The track didn't dry out completely, however, so how relevant the times are is a moot point.

Rubens Barrichello was fourth fastest for Ferrari, a tenth off Trulli's pace, while Fernando Alonso was fifth quickest in the second Renault. The Toyota duo of Cristiano da Matta and Olivier Panis were next up, ahead of the Sauber of Heinz-Harald Frentzen and the Jaguars of Mark Webber and Justin Wilson.

Conspicuous by their absence were the McLaren pairing of Kimi Raikkonen and David Coulthard, who only completed their installation laps and weren't seen out on track again.