BEIJING, China -- Mike Day of the United States is leading the first-ever Olympic BMX competition after Wednesday's quarterfinal round in the men's group.

France's Anne-Caroline Chausson is in first for the women heading into the semifinal round.

The Beijing Olympics mark the first time medals are being awarded in BMX, an event that is basically a race, but one that also features high technical jumps and other obstacles to challenge riders.

Day had the best time of the eight riders in his heat in all three runs, giving him a rank score of three. The lowest score is best as riders receive a point equal to their finish position in a given race.

Australia's Jared Graves had the next best ranking score of four after finishing first twice and second in the other run of Heat 4. Sifiso Nhlapo of South Africa and Latvia's Arturs Matisons tied in the second heat with six points each and Maris Strombergs, another Latvian rider, won Heat 3 with seven points.

Donny Robinson and Kyle Bennett of the U.S. also qualified for Thursday's action, which features both semifinals and the final round.

Chausson was first in women's seeding phase, posting the best time of the day with a run of 36.660 seconds. Great Britain's Shanaze Reade, the two-time reigning BMX champion, was second with a time of 36.882 seconds.

American rider Jill Kitner, who is competing with a torn ACL, qualified for Thursday's semifinal round with the seventh-best time.