Two rematches headline the Manny Pacquiao vs. Mario Barrios undercard, while former champions and young contenders look to impress. Here's a breakdown of all the action on the Pacquiao vs. Barrios card.

One of the greatest fighters of the past 30 years is set to return to the ring on July 19 when Manny Pacquiao ends his retirement to face Mario Barrios. Pacquiao will be looking to add to his legendary resume by picking up another championship as Barrios' WBC welterweight title will be on the line.