if your opponent always plays that same tactic, and he is better on all fronts, you might try something extreme as well.
I didn't do that myself, since I didn't have the need yet, but If I where in your place I'd field 5 outside players (yes even at PF and C positions) and play motion or run and gun (since he always defends 2-3 anyway), and probably would go for a man to man or 3-2 defense...
It probably won't win you the game, but it sure will be a surprise, and you never know. ;)
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