When the play calling screen appears while on defense, look at the CPU's section of the screen. It will read 3 WR 1TE 1RB (or something similar). Pick your defense accordingly. If it reads 2WR 1TE 2RB, try a 5-2 defense. If it reads 3WR 1TE 1RB, play a nickel package. If it reads 4WR 0TE 1RB, play a dime. Try various defense formations to make sure all the wide receivers are covered and you can potentially stop a run (if the CPU calls a run). You will win many more games by doing this.