Hi. I'm making a simple football emulation where there are 3 players, a running back, a defender, and a blocker. The player is the running back and tries to score while the defender tries to catch him. Simple. So anyways, I need a system where the defender will try to avoid the blocker and get to the running back. I was wondering if people could brain storm some ideas for me. Thanks.

I did almost exactly this a long while ago using a simple combinaison of a goal-oriented AI and steering behaviors. The goal-oriented AI was to allow the players to switch roles, to handle the ball-carrier logic and to manage some team coordination. The steering behavior elegantly manage the movement logic.

An AI vs AI game looks like this. Sorry the video is so lousy, I was just fooling around with Torque at the time.