Five keys for Manny Pacquiao

— -- In a fight that should have a lot to say about his immediate future in the sport, Manny Pacquiao will look to regain his welterweight title and prove the validity of his career in Saturday's rematch against Timothy Bradley Jr. at the MGM Grand Garden Arena in Las Vegas.

Pacquiao  Freddie Roach, Pacquiao's acclaimed trainer, has a lot at stake in this fight. Any time an aging fighter enters a big bout, the possibility of retirement if he should lose hangs in the balance. Winning is not only an option in the rematch with Bradley, it's an obligation. A victory for Pacquiao will depend a lot on what Roach has planned and how well he has prepared his fighter physically to counter his opponent's strategy.