The belly series can also have a number of alternatives. The key man is the quarterback, who decides what's going to happen. He does not make his decision in the huddle, but only after the play has started and the defense has committed itself. After getting the snap from center, the quarterback takes a step back and thrusts the ball into the stomach of the fullback. If defenders begin to tackle the fullback, the quarterback withdraws the ball. He can then run or pass with it. On a further option, the quarterback can pitch out to a halfback, who, in turn, can try to blits around end or pass downfield.

When the belly series works, it's a thing of beauty. But success hinges on the quickness of the quarterback. He must react to the development of the defense and choose his option in a split second.

The third major series is the run-pass option. On this play, the quaterback gets the snap and "rolls out" (runs towards the sidelines) behind a wall of blockers. He can either run or throw, depending on how clear his pass receivers are. Harvard got most of its passing yardage with this play last Saturday.

In the Massachusetts' game, it was the defense that really excelled. What is the philosophy here?

Harvard uses two very similar defensive formations, the "Oklahoma" and the "eagle." In both defenses, only three of the eleven men are down in a four-point or crouched stance; the rest are on their feet. Yovicsin says this means greater pursuit power, or the ability to get tacklers to ball-carrier more quickly. As last Saturday's game showed, their success depends on alert, aggressive linebackers.

Over the season, look for more and better Harvard passing and its traditional hard running and stout defense. With a few breaks, the 1963 team could upset preseason polls quite easily.