ANNAPOLIS, Md.--As Harvard was smoking Navy midway through the singles competition here Saturday, a spectator sidled up to Navy coach Bobby Bayliss--one of the classiest guys in college tennis--and asked him how his team was doing this year.

"Well, we were 6-0," Bayliss said.

"You mean you had some other matches after that?"

"No," Bayliss responded, "we were 6-0 until this match."

By the end of the afternoon, though, Bayliss's humility had proved unfounded. The Midshipmen kept their 1979 record perfect by stunning the Crimson, 5-4, on Navy's windswept outdoor courts. It was the biggest upset in Eastern League tennis since Harvard defeated Princeton in 1976.

The loss shattered Harvard's hopes for its first undisputed league crown since 1966, and it made a clean sweep of the Crimson's eight remaining league contests necessary for even a share of the title. Navy had not beaten Harvard since 1971, when Harvard coach Dave Fish was playing as a junior.

"Sure, we're upset," captain Kevin Shaw said after the match, "but it doesn't affect our season too adversely, because one way or another we still had to beat Yale and Princeton."

Although Harvard stormed out to a commanding lead early in the singles, the Middies turned it around and tied the score at two-apiece after the completion of four matches.

Third man Bob Horne and fourth man Kevin Shaw continued to have trouble playing in the wind (they both lost at Maryland the previous day), each dropping a decisive straight-setter.

Dick Arnos, however, subbing at six due to injuries to Scott Walker and Jim Curley, won an equally important straight-setter. And five-man Greg Kirsch avenged his loss to Jon Wall of a year ago by search-and-destroying the Middie, 6-2, 6-1. The victory gave the red-hot Kirsch a weekend total of 29 games won, 10 lost.

Not Enough

The Middies moved one ahead when their tough two-man. Gene Miller, edged Harvard's Andy Chaikovsky--who was serving softballs due to a sore shoulder--on a three-all point at 5-4 of the third set.

Miracle man Don Pompan evened the team match at three-apiece heading in to the doubles, though, resorting to his patented third-set lightning in dispatching highly-touted plebe Dave Andrews, 6-2, 4-6, 6-2.

After the second and third doubles teams swapped victories, the outcome of the afternoon--and indeed, the course of the season--hinged on the first doubles battle between Chaikovsky-Pompan and Miller-Andrews.

The Crimson duo came back from a three-love deficit to even the final set at three-apiece, then threatened to break Navy's serve when it won the first three points of the seventh game.