The consistent failure of underdogs in professional sports to even try something new suggests, to me, that there is something fundamentally wrong with the incentive structure of the leagues.
This pretty sums up why I generally don't watch professional sports. I love basketball, but the way that it is played in the NBA is so conservative that it's about as interesting as watching paint dry.
I would love to see the pro sports leagues implement financial incentives in order to reward teams that are taking risks. The only organization I know that does this is the UFC (via their "Fight of the Night", "Knockout of the Night" and "Submission of the Night" bonuses), and perhaps not coincidentally, that is the only sport I find interesting enough to watch on a regular basis.