Stop Marinaro and you stop Cornel1. Harvard's football team couldn't do it last Saturday, and on a horrible afternoon at Ithaca, when its offense sputtered and its defense collapsed, the Crimson watched its Ivy championship defense crumble, 41-24.

Sophomore tailback Ed Marinaro ran wild for the Big Red, scoring five touchdowns and piling up 281 yards against Harvard's previously impregnable defense. It would have been asking a lot to expect even a consistent, explosive offense to compensate for such a performance, and the Crimson's attack was neither.

In several respects, the Crimson's trouncing of Columbia a week ago hurt it last Saturday. The loss to Boston University had planted a lingering suspicion that Harvard's offense was not nearly as effective as it was supposed to be. But the scoring orgy last week submerged that suspicion.

So at Ithaca, when the Crimson stalled on occasions when it had to run consistently and control the ball, it proved that a tough defense is now, more than ever, and absolute necessity if Harvard is to have a successful season.

And the Crimson's defense is no longer immovable. It was able to balance Har-vard's lack of scoring power for the first two games, and it stifled Columbia's passing attack last week.

But yesterday, Harvard had to stop Ed Marinaro. Maninaro was expected to pick up his share of yardage, which is now the largest share in the nation, and he did.

For the first time this season. Cornell also came up with a cohesive, diversified attack, using quarterbacks Rick Furbush and Bill Arthur to tremendous advantage on running plays, and. when it had to piercing the Crimson secondary for crucial passing yardage. From the first, it was evident that Harvard could not stop both threats.

Offense Stalled

The Big Red stalled Harvard's opening series of downs with an interception on the Cornell 20, and in five plays moved to the Crimson 41. On the next play, Marinaro broke loose bucking, twisting and sprinting for a touchdown.

Cornell stopped Harvard again, and this time with Marinaro carrying on six of the 10 plays, marched to the Crimson 12. But safety Neil Hurley picked off a hurried Furbush pass in the end zone on the next down, and escaped 102 yards down the left sideline for a touchdown. It was the third longest interception return in Harvard history, it rescued the Crimson from trouble, and it tied the game.

Half Throttle

But even by then it was obvious-Harvard was going to be in serious defensive trouble all afternoon unless it could throttle Marinaro, or at least hamper him and shut off the rest of the Cornell offense. Eventually it did both- about half as well as it had to.

Harvard crushed Marinaro on three consecutive carries late in the first period, took possession, and moved to the Cornell 13 in 10 plays, where Richie Szaro booted a field goal to put the Crimson in front.

Then came the first Cornell eruption. Midway through the second quarter Harvard's Gary Singleterry punted out of the Big Red end zone, but on first down Marinaro broke free for 43 yards around right end. Seven plays later, the Ithacans were on the Harvard two and Marinaro slammed over for his second touchdown.

A short punt gave Cornell possession near midfield a major penalty on Harvard moved the Big Red to the 12. and on a long third-down play. Marinaro fought his way into the end zone. It was Cornell 21 Harvard 10.

Time to Come Back

By the third period. it was clearly time for the Crimson's patented comeback. It took Harvard just five minutes to go ahead.

Cornell took the second half kickoff. stalled, and punted to the Harvard 39. In six plays, quarterback Dave Smith moved the Crimson to the Big Red 29, and halfback Ray Hornblower broke two tackles and eluded the Cornell secondary to score on the next down.

Seconds later, safety Walter Johnson intercepted a Furbush pass to put Harvard in scoring position again and Hornblower scored from the three-yard line four plays later. Harvard was leading now 24-21.

But the Crimson defense had yet to develop an effective method of strangling the Marinaro threat, and Cornell matched 30 yards, with Marinaro gaining 55 of them, for another touchdown.

By now, Harvard's offense had been overextended. The Crimson gained possession three times in the final period-and three times yielded without a first down.

Ties Ivy Record

And the Crimson defense, on a crucial third-and-11 play at the Big Red 32 allowed Furbush to escape up the right side for 18 yards and the first down. Five plays later. Marinaro broke across for another touchdown, his fifth to tie the Ivy record for most in one game.

Marinaro was taken out of action then, but Harvard was beaten. With four minutes remaining, the Cornell substitutes began an 80-yard drive, and Arthur threw 14 yards to sophomore Ron Mower for the final touchdown. There were 10 seconds left.

Cornell had won its first game of the season, and had beaten Harvard for the first time since 1962.

So now, unless Harvard upsets undefeated Dartmouth next week, its chances of defending the Ivy League championship are nearly hopeless. The Crimson needs to adjust both its offense and defense drastically, and mid-October is no time to begin such a task.