Praying only works if the other guy does not pray. So, if Manny prays to god for a victory, you have to counter that tactic by praying to a deity of equal or greater value. So if Manny prayed to God, to beat him you should pray to Buddah or Dr. Zaius. If both men pray to gods of equal value, then the fight will be decided by who trained harder, who has the better natural ability (which is a direct result of how hard your parents prayed when you were born), and dumb luck (which can be obtained through sacred charms such as rabbits feet, four leafed clovers, a kiss from Anne Hathaway, etc). Finally, when seeking a victory it is also important to purchase insurance should the bout go the distance. This can come in the form of a few thousand dollars slipped into the pocket of one of the judges.
From Manny's comments I venture a guess and say he thinks God allows trivial things like sporting events play out on their own course while he's busy taking care of things far more important. And I tend to agree with him.