Hakkinen

The Finn, who is due to start on the front row with Ferrari's world champion Michael Schumacher, tracked over the grass run-off and crunched into the metal barriers a minute from the end.

He stepped out of the car unhurt and the team later reported that the moderate damage to the right front side could be repaired before the race.

The session had earlier been interrupted for 15 minutes when Colombian Juan Pablo Montoya, winner of the last race in Italy, suffered a blown engine in the spare Williams.

Smoke billowed out of Montoya's BMW-powered car as he sped down the main straight, eight minutes into the session.

He parked the car by the pit lane wall but the clean-up operation took longer than expected due to metal debris on the track.

"I think probably being the first lap for the car with that engine, it's probably some sort of installation or build problem," said Williams technical director Patrick Head. "We've run reliably in practice so we should be okay. But in this business, you never know."

When the action resumed, Brazilian Rubens Barrichello beached his Ferrari in the gravel trap while Ralf Schumacher spun his Williams before continuing.

Germany's Heinz-Harald Frentzen pulled over in the Prost at the same time as Hakkinen's accident.

France's Olivier Panis stalled at the pit lane exit early on and later appeared to damage his BAR as he ran over a curb.

Ralf Schumacher was fastest in one minute 13.912 seconds, ahead of the McLarens of David Coulthard and Hakkinen. Michael Schumacher was fourth quickest.

Schumacher considered retirement
Michael Schumacher was close to retiring from Formula One following the September 11 attacks on New York and Washington.

The concerns of the German who drives for Ferrari were revealed by the Italian team's technical director Ross Brawn on BBC radio.

Speaking a few hours before the United States Grand Prix in Indianapolis, Brawn said Schumacher had been deeply affected at the Italian Grand Prix which took place in Monza only a few days after the attacks.

"When he arrived in Indianapolis he was still feeling the effects of Monza," said Brawn.

"He really was badly affected by the disaster. There was talk of retirement. I think a few days of consideration reminded him how much he loves racing."