Harvard crushed an inexperienced Penn team, 13-3, Saturday on the Business School Field in its Ivy League Lacrosse opener, sparking optimism that the Crimson can upset talented Cornell next weekend at Ithaca.

The victory upped Harvard's record to 2-1. During an abbreviated Southern trip last week, the Crimson downed Rutgers, 7-6, in double overtime, and then lost the next day to powerful Navy, 8-3.

The Penn game was a runaway by the midpoint of the second period. Attackmen Steve Milliken and Phil Zuckerman were the top scorers Saturday, helping Harvard to an 8-2 halftime lead. Both had four goals, and Zuckerman added three assists.

The Crimson's strength has clearly been its depth. Coach Bruce Munro is rotating four midfields, and in fact, the fourth one has outscored all the others with five goals. The first three have two each. On defense, Munro is using six men to ease the strain on injured starters, Don Gogel and Charlie Kittredge.

Harvard's balance was most apparent in the game at Rutgers Tuesday. Seven different men collected the Crimson's goals, with sophomore midfielder John Hagerty putting in the winner after four minutes of the second five-minute overtime. Earlier in the game, which was played in sleet, the Crimson had blown a 4-1 lead.

Harvard is still suffering from an inability to stave off its opponent during man-down situations. Against Navy, the Crimson was penalized 16 minutes, and the disciplined Navy offense put in five goals on the same man-up play. These tallies helped the Midshipmen build up an early 6-2 lead which Harvard could not overcome.

The Crimson is the definite underdog Saturday at Ithaca. Cornell has dominated Ivy League lacrosse, winning the title last year while going undefeated. Runnerup Brown lost to the Big Red, 20-6, Harvard was defeated, 13-6.

Cornell no longer has Mark Webster, the top scorer in the University's history, but attackman Al Rimmer, the Ivy scoring champion, is back, as are midfielder Bob Shaw and goalie Bob Rule. As usual, a good group of sophomores gives the Big Red appreciable depth.