Simoncelli maintains challenge

World champion Marco Simoncelli maintained his push to retain the crown by winning FIM 250cc race at Indianapolis.

The Metis Gilera rider finished two seconds ahead of current championship leader Hiroshi Aoyama of Scot Racing Team to record his fourth win of 2009.

The Italian, who races on home turf at Misano next weekend, began third on the grid after a difficult day's work on Saturday but fought his way through to move 27 points behind his Japanese rival.

Simoncelli was aided by a moment of misfortune for Aoyama four laps from the end when he suffered a big front end wobble to lose ground.

Alvaro Bautista of Mapfre Aspar finished third with Mike di Meglio, who started on pole, fourth.