PRINCETON, N.J. April 26--The Harvard tennis team upset a powerful Princeton squad, 5-4, today to retain a chance for first place in the Eastern Intercollegiate Tennis Association. The netmen are now counting on tre Tigers to beat Penn, so that all three teams can tie for first place, as they did last year.

Almost 300 spectators watched the outdoor portion of this 6-hour marathon battle, which began in cloudless, calm 70-degree weather, and was moved indoors as daylight disappeared. The contest continued on indoor courts in Princeton's new Jadwin Cage.

Enjoying the best tennis weather since the Southern trip, the Crimson won four of the six singles matches. At Jadwin Cage, where about 100 faithful spectators remained, Harvard captured the number three doubles to gain this EITA victory.

The turning point of the battle was Rocky Jarvis's spectacular victory over previously undefeated junior Rich Howell. Howell, a baseline player, rarely charged the net, and the match dragged out for more than three hours. Jarvis ended up on top, 3-9, 9-7, 6-4.

Terry Oxford teamed up with Larry Terrell to win the Crimson's number three doubles match for the deciding point. Both Tigermen in this doubles match were sophomores and were under the pressure of knowing that Princeton's fortunes hinged on their play. The Tigers's Rogers and John Kayser, the number eight singles player, fell 6-2, 3-6, 3-6, in another marathon match.

In Jarvis's struggle for the number two singles, he was down match point a few times, and fought back from a triple match point deficit in one game. Jarvis's comeback in the second set disturbed the usually cool Howell, who made increasingly loud comments. But Jarvis stayed calm, sometimes smiling when he missed a difficult shot.

In the third set, after Jarvis had broken Howell's service, 3-2, Howell charged the net, missed, and got cramps in both his thighs. The match continued ten minutes later, and Jarvis finished off Howell, who was limping slightly and had slowed up.

Weakest

The Tigers were weakest in their lower singles slots, and Harvard swept the bottom three positions.

Larry Terrell beat Scott Rogers at number four with a 6-3, 6-8, 6-4 score, and number five Bill Washauer defeated Rick Weir with an extraordinary comeback, 4-6, 9-7, 6-2. Fully-recuperated Chris Nielsen had little trouble in the sixth spot against Andy Krusen and won, 6-4, 6-1.

Princeton's two singles wins were by number one Bobby Goeltz, a junior, an Interscholastic Champion for three straight years during high school, and Tiger captain Win Irwin, the only senior on the Princeton team.

Crimson captain John Levin fell, 5-7, 4-6, to Goeltz, after having set point in the first set. Goeltz got Levin to run from side Confident of his own fast reactions, to side, and Goeltz, with a very smooth style, was able to return almost anything. Goeltz stood in close, even when receiving Levin's first serves.

Terry Oxford could not get used to aggressive Tiger captain Win Irwin and was defeated, 2-6, 4-6.

The Tigers captured the number one and two doubles. Levin and Jarvis succumbed, 7-5, 2-6, 4-6. The number two doubles team of Neilsen and Washauer was defeated, 4-6, 1-6.

Tiger coach John Conroy said, "Harvard was really up and hungry for it." He compared today's upset with the 1965 contest, when Princeton, favored to win, hosted Harvard but lost to the Crimson team, 4-5. In that contest, the Tigers won four of the singles but lost all three doubles.

Conroy pointed out that the top three Harvard netmen are seniors. He also mentioned Tiger freshman Bill Colson, number four in the 18 years and younger national competition, whom he predicts will move to number one ahead of Goeltz next season. "There will be another year. We'll be back," Conroy said.