So I just lost a bet that I placed "live" after a tennis match has started.  It appears that the player I bet on retired after I placed the bet and then the bet counts as a loss.  The rules say if one set is completed then the bets will stand.  I bet this match in the second set and the player retired in the third set. 

Other online betting sites I usually play at say if you bet live tennis then the match must complete, without retirements.  However, at directbet, you can apparently wait until you see a player hurt in the second or third set and then bet the other guy, and you'll win.  Seems like a weird rule setup, but hopefully someone can take advantage of it.