IRVINE, Calif. (AP) _ Six national championships and membership on the U.S. National Team will be at stake this week during the Phillips 66 Diving Championships at the Heritage Park Aquatics Complex.

Among the 120 entries in the five-day competition are 1984 Olympic gold medalist Greg Louganis, the defending national champion in men's platform diving, and Wendy Williams, the defending national champion in women's platform diving.

Competition will be held in one-meter springboard diving, three-meter springboard diving and 10-meter platform diving.

The meet begins Wednesday and concludes Sunday. The finals in the men's one-meter competition will be held Thursday afternoon while the finals in the women's one-meter competition will be held Friday afternoon.

On Saturday, the finals in the men's and women's three-meter competition will be held, while on Sunday, the finals in the men's and women's platform diving will be held.

The Olympic Trials are scheduled Aug. 17-21 in Indianapolis. The top eight divers from the three-meter springboard and platform events will be invited to eompete in the Trials.

Joining Louganis as top contenders in the men's competition are Bruce Kimball, the 1984 Olympic silver medalist in the platform diving; Matt Scoggin, who beat Louganis last month in the platform event in a pre-Olympic meet; Ron Meyer, the defending national champion in the three-meter event, and Mark Bradshaw, the defending national champion in the one-meter event.

Joining Williams as top contenders in the women's competition are Mary Fischbach, the defending one-meter champion and NCAA titlist this past year in both the one and three-meter competitions; Tristan Baker-Schultz, the defending champion in the three-meter event, and 1984 Olympians Michele Mitchell and Wendy Wyland.

Kelly McCormick, the 1984 silver medalist in the three-meter event, was forced to withdraw from this competition because she reinjured her left calf muscle early this month.

The meet begins Wednesday with preliminary competition in the women's three-meter event and men's platform competition.