Pacquiao is undefeated with a 2-0-1 record against his rival, but all three fights have been close.
Is another close decision at hand or will either fighter shock the other with a barrage of punches that leads to a knockout?
Fight fans have been waiting for this bout since their third fight last year. It's not only just the fight itself that fans are waiting for. There are several storylines that fans are expecting to unfold as Pacquiao and Marquez battle.