Only BAR test driver Anthony Davidson managed to get within touching distance of the Ferraris, with Barrichello topping the standings ahead of his six-times world champion team-mate.

The Brazilian clocked one minute 11.354 seconds for the 4.192km circuit affectionately known as "The Brickyard", a time just over a 10th of a second quicker than the fastest race lap set by Schumacher last year.

The 35-year-old German was 0.265secs off, with Davidson underlining the potential strength of the BAR at this track as he finished third quickest and just over three-tenths adrift.

Juan Pablo Montoya at least offered some resistance with a 1:12.008 lap in his BMW Williams, with Toyota and Jaguar test drivers Ricardo Zonta and Bjorn Wirdheim fifth and sixth on the time sheets.

Jenson Button was 1.2secs off the pace in seventh in his BAR, followed by the Sauber of Giancarlo Fisichella, Olivier Panis in his Toyota and Ralf Schumacher in the second BMW Williams completing the top 10.

David Coulthard was down in 18th in his McLaren, 2.5secs down and eight-tenths off team-mate Kimi Raikkonen who was 12th.

There was one minor incident when Gianmaria Bruni spun coming out of turn eight on the tight, tricky infield section, and stalled his Minardi in the middle of the track.

It resulted in a four-minute delay to the session as the car needed to be crane-lifted out of the way.