I don't think there's an issue from just playing basketball. But you are slightly more likely to pick up injuries in a game than you are in training. Unfamiliar opponents, playing against people who won't pull out of a potentially dangerous situation because they aren't your friends and its a competitive game, etc etc.

Actually playing 40 minutes, especially with the number of timeouts in the college game I don't see as being a problem at all.

Delly probably grew up playing at least a little bit of either AFL, Mitch and Jordy may well have played rugby. Rugby is two forty minute halves with no timeouts. AFL is four 25-30 minute quarters with no timeouts. Both are full contact. There is very little down time in either game (maybe 60 seconds after a score, but you spend half of that running/jogging back into position). 20 minute halves, with regular stoppages shouldn't be a problem as far as just aerobic fatigue goes.