US Grand Prix organisers said they were considering the future of the Formula One event at Indianapolis after angry fans witnessed a 'race' of just six cars on Sunday.

"We are as disappointed as we've ever been in hosting an event here," Indianapolis Motor Speedway president Joie Chitwood told reporters.

• Race report: Michael Schumacher wins boycott-hit US GP

"We pride ourselves on what we do and that's to be an international leader in motorsports entertainment. Today had nothing to do with being a leader of motorsports.

"We'll be evaluating our position on what's going to happen in the future," he added.

The famed Brickyard, home of the Indy 500, has hosted a Grand Prix since 2000 and an estimated 120,000 people bought tickets for Sunday's race. There is one year remaining on the contract.

Sunday was blighted after seven of the 10 teams pulled into the pit lane after the formation lap and did not race because of concern about their Michelin tyres.

The teams had pleaded in vain for an extra chicane before the final banked corner to slow down the cars after Michelin said they could not otherwise guarantee the tyres would withstand more than a few laps.

Indianapolis Motor Speedway chief executive Tony George had earlier issued a statement listing the addresses of Michelin, the International Automobile Federation (FIA) ruling body and Bernie Ecclestone's Formula One Management for angry fans to complain to.

HOLLOW WIN

Fans threw bottles and cans on the track during the race and many booed and whistled during the podium ceremony, some chanting "Bullshit, Bullshit".

Ferrari's [Images] Michael Schumacher [Images] was the winner, ending the champion's run of nine races without success with the most hollow victory of his career.

Chitwood, said he and the Speedway authorities were "monumentally disappointed" and surprised as anyone by the events of the day.

He said he could not recall any event at the circuit where fans had been as outraged.

"To say it's a disappointment is an understatement," Chitwood declared, before expressing how damaging the day's events were for the race's future.

"No-one at the Indianapolis Motor Speedway is proud of what occurred today," he added.

"Undoubtedly this sets us back in all of our efforts or all of the gains we've made in introducing this sport to America. I would say it is a major setback.

"I can tell you this, we feel as victimised as the fans do in what they witnessed today.

"I think there is a responsibility to be prepared for this event. We did our best in three weeks to convert from an oval track to a road course and we were prepared for this event. I wish everyone had been prepared for this event.

"Obviously not everyone was prepared today and I think that's inexcusable."

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