American University can clinch a home-court advantage in the first round of the East Coast Conference playoffs by beating St. Joseph's in an 8 o'clock basketball game tonight at Fort Myer.

The Eagles have two league games remaining, finishing the regular season Saturday against Temple, and will host a first-round game Monday night if they win either. If they lose both, the Eagles will play at Hofstra Monday night.

St. Joseph's, under the former AU coach, Jim Lynam, is playing its best basketball of the season, having won seven straight and 10 of its past 11, and has risen into the Widmer Cup eastern rankings for the first time.

The Hawks (17-7) are led by center Marcellus (Boo) Williams, which means this game is sure to be a Boo Boo, since AU's star player is Russell (Boo) Bowers, the nation's ninth-leading scorer with a 26.5 average. r

Lynam, who recruited Bowers and left prior to last season after five years at Ward Circle, devised a nifty zone defense for last season's game. It helped hold Bowers to 13 points in St. Joe's 70-61 victory in Philadelphia.

The 6-foot-5 forward has not scored fewer points in the 31 games since then.

AU has won four of its last five to improve to 13-11, having won its last two with a defense that held opponenets to 38.3 percent shooting.

Meanwhile, the men's Maryland junior college tournament, with 13 teams, opens at 1 p.m. at Prince George's Community College. Baltimore CC, Prince George's and Alleghany CC drew byes as the top three seeds.

The five games today send Harford against Montgomery-Takoma Park at 1, Catonsville vs. Essex at 3, Anne Arundel vs. Charles at 5, Montgomery-Rockville vs. Frederick at 7 and Howard vs. Hagerstown at 9.

The semifinals begin Friday at 2 p.m.