American University won its first championship, in any sport, in the six years of the East Coast Conference yesterday as the Eagles blitzed Rider College of Lawrenceville, N.J., 3-0 in the soccer title game at American.

In improving its unbeaten streak to 16 and its season record to 14-2-4 on a muddy field, American slipped and slid through second-half rain to register its sixth straight shutout and 12th this fall.

American plays an NCAA quarterfinal game Sunday at Clemson. The Eagles edged Virginia, 1-0, last week in the South Atlantic Regional final of that tournament.

"We're very competitive, but I'm realistic enough to know that any team can beat us in the playoffs," said AU Coach Pete Mehlert. "We have already accomplished a lot more than people expected from us."

American accomplished its latest deed without two starting backs. Scott Turner was out with a bad ankle and Alex Kozlov was ill was mononucleosis. Despite their absence, goalie Bill Ruvo posted his ninth shutout in 14 games.

"I've had some good seasons," said the former junior college goalie, "but this means a lot more, playing Division I NCAA soccer."

Ruvo needed to make only four saves, the first coming moments after AU's scoring machine, freshman Mark DeBlois from McLean, had pushed the Eagles into a 1-0 lead at the 33:13 mark of the first half. A cross by Luis Calderon set up DeBois' 13th goal.

AU had missed three chances earlier, Doug Dugan's header hitting the crossbar while Kevin Barth was stopped cold by Rider goalie Bill Ireland on two point-blank shots.

"I wasn't worried, we were playing good soccer," Mehlert said. "I knew the goals would come and our defense was playing well.

"They're (his defenders) honest players, they work hard, they're intelligent and mark their players tight. It makes our sweeper's (Charlie Davis) job a lot easier. We have the right chemistry."

Mehlert relaced his two missing backs with junior Terry schrider and Keith Tabatznik. Tom Tague completed the backfield unit.

Rider, which finished at 10-7-2 after winning the ECC's West Section, went on the offensive to start the second half, bringing the backs to midfield. wBut Barth's goal at 67:33 seemed to defuse the Broncos.

"It was a set play," Mehlert noted. "First DeBlois and (Jim) Piedmont cleared space and Dugan then chipped it to Barth. Just like a backdoor play in basketball."

Thirteen minutes later, AU had its third goal, thanks to an assist by Rider back Ruben Rivera.

Barth, a sophomore from Jefferson High in Alexandria who was AU's leading scorer a year ago, sent a long cross from the left corner.

The ball came down to the left of Ireland. Dungan and Rivera collided with the ball, knocking it into the goal.

For the third time, Rider has failed to win an ECC title. The Broncos reached the final in 1975 and 1978, only to lose to Temple both times, 1-0, AU beat Temple, 1-0 in a shootout, Nov. 15 to win the ECC East Section crown.