The Harvard freshman football team trimmed Yale 18-3 yesterday after both squad's vaunted passing attacks went sour.

Skillful defense confined Harvard's Rick Zimmerman to 4 completions in 17 attempts and Yale's Billy Gales to 6 out of 20, but the Crimson picked up the slack with a rushing offense led by halfbacks Don Sadoski and Ron Kram.

In the third quarter, with the Yardlings holding a thin 6-3 lead after a 25-yard field goal by Yale's Jeremy Kinney, Kram took Kinney's kickoff and dashed to the Ell 49. Two plays later. Sadoski found no room over right tackle, sprinted around the left end instead, and completed a 45-touchdown run.

56-Yard Drive

The Crimson took advantage of Zimmerman's only moment of passing effectiveness to score their first touchdown. Late in the first half, Sadoski intercepted a Gales pass on the Harvard 44. Zimmerman then took the team 56 yards in nine plays, chiefly by pitching to Sadoski for 11 yards, to Kram for 19, and finally seven yards to Bill Cobb, who leaped out of a ruck of Yale defenders to grab the pass and score.

Harvard's last touchdown came in the fourth period when the Crimson's Alan Bersin blocked an attempted punt by Bob Ternes of Yale. Bob Brooks, a Yardling tackle plucked the ball up and scampered the last 15 yards to the goal line.

The cold weather may have had something to do with the quarterbacks' ineffectiveness, but Zimmerman's own particular gremlin was Dan Begel, a Yale back who intercepted one of his passes and broke up several others. Zimmerman redeemed himself by running a number of quarterback sneaks for big gains, adding a good deal to the Crimson's total of 193 yards rushing.

The Harvard squad celebrated a 5-1 season by providing a beer shower for Coach Henry Lamar after the game. The loss evened Yale's record at 3 and 3.

The Crimson enjoyed complete mastery of Ivy League opponents this year, defeating Princeton, Dartmouth, Brown.