For defense, use Zone Home which is the first play when you push left on the joypad. Push the button three times to select the left cornerback (I assume he's a cornerback but he could be a safety). When the play snaps, don't move your guy. If he throws toward your side, just move your guy leftward (your left, not his). You're guaranteed an interception. If he throws to the right, the computer will intercept for you or he'll complete a short gain which is useless.
If the computer picks a running play where the running back is right up on the line, push the button seven times so that you are right up on the line near the center. At the hike, run up to meet the line, then immediately run diagonally to the right. This might take getting used to. The running back will follow you! I usually stop within the 5 yard line so that the running back tackles me. The computer's had like 50 yard losses trying to tackle my defensive guy.
When the back is punted, leave the mark on the current guy (don't switch to another guy). When the ball is hiked, just let your guy stand there. When your guy receives the ball, run diagonally to the left and you'll get a touchdown 65% of the time (well, if the computer seems super accelerated, you have to run diagonally to the right and you won't get a TD.)
The computer is so stupid. The way the defensive guys can run right over the offensive line is absurd.
Well, the offensive play is Gun Men which is the first play when pushing the pad left. Just use your two receivers on the left side. If it's a defense like:
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throw to the second receiver from the left by centering the cursor just about
the left safety. For heavy blitzes use the second receiver from the left. If
the computer gives me one of its usual defenses, I try to throw to the far
left receiver so that I get 20,30 yard gains while stop the clock. Using the
9 timeouts is key...If they use that bizarre defense where everyone seems scattered randomly, move the cursor up about 15 yards and 5 yards to left of center and release when they are about to hit the quarterback.
Oh, usually you get the most yards when the QB is about to be slaughtered, especially blitzes.
I really only get picked off when I try to get really fancy and want to have some stupid fun...