Michael Schumacher makes it eight wins out of nine

The most serious of the three involved Schumacher's brother Ralf, who crashed heavily at the banked final turn.

The Williams hit the wall at 90 degrees at close to full speed and there were some fears that the German had been badly hurt when he failed to climb out of the car.

Mercifully, it has since emerged that he has escaped serious injury, although he is suffering from concussion. He has been taken to the Methodist Hospital in downtown Indianapolis for a precautionary CAT scan.

Ralf's shunt was the third in the first dozen laps of the race.

The first incident came just seconds in. Christian Klien ran into the back of Cristiano da Matta's Toyota, which had slowed with gearbox gremlins, on the exit of turn one.

The Jaguar speared across the track, leaving Felipe Massa, Giorgio Pantano and Gianmaria Bruni with nowhere to go. All four cars were eliminated on the spot.

The safety car was brought out for four laps, and Schumacher took his chance to get past pole man Michael Schumacher at the restart. The German timed his run to perfection to drag past his team-mate on the way down to turn one.

Three laps later, there was another accident, this time involving Fernando Alonso. The Spaniard had made a blinding start to go from ninth to third but crashed out on lap eight after his right-rear tyre failed under braking at turn one.

The incident cleared up without need for the safety car - but it was needed when Ralf crashed a couple of laps earlier.

It took some time for the medical car to arrive on the scene, but when it did, F1 doctor Sid Watkins transferred Ralf to a stretcher and a neck brace was fitted.

The cars spent nine laps under the safety car, with leader Michael Schumacher understandably glancing right every time he passed the incident for any indication of his brother's condition.

Crazily, the safety car led the field through the debris of the accident for lap after lap, rather than going through the pitlane.

Schumacher, Raikkonen, Barrichello and Trulli all stopped under the safety car but a number of other runners, including the BARs of Button and Sato, did not.

This turned out to be a big blunder as both cars as both cars were forced to stop just a handful of laps after the restart.

Button's race ended soon after with gearbox problems but clearly Sato could have been a contender for victory had his team not botched the strategy.

By Button's estimation the BAR was the best car on the track and Sato set a scorching pace in the middle of race.

The Japanese driver eventually finished third, his first ever podium, but it could have been so much better.

Not surprisingly for such an incident-packed race, there was an exceptionally high rate of attrition. Only eight cars made it to the finish.

Aside from those cars eliminated in the early crashes, a number retired with mechanical failures.

And Williams suffered their third disqualification in the space of a week when Juan Pablo Montoya was black-flagged in the closing stages of the race.

The Colombian's race car would not start so he abandoned it on the grid and switched to the spare. Unfortunately, he was just seconds too slow in his efforts to get off the track so was thrown out.

The result of this was the fact that, as in Canada, there were a few unexpected points scorers.

Jarno Trulli, who had started last after suffering a mechanical problem in qualifying, moved all the way up to fourth place while Olivier Panis celebrated his 150th race with a strong fifth place.

Remarkably, for a race in which there were so few finishers, McLaren managed to get both cars to the finish. Kimi Raikkonen, who was forced to make an unscheduled stop with an electrical glitch, was sixth with David Coulthard seventh.

Few people could begrudge the fact that the final point went to Minardi's Zsolt Baumgartner.

It was the team's first point for more than two years while Baumgartner becomes the first Hungarian ever to score an F1 point.

Minardi's celebrations - and the positive news over Ralf's condition - meant one of the most dramatic races in years had a happy ending.