Should Juan Manuel Marquez lose to Floyd Mayweather Jr. on September 19, the WBO will mandate that the Mexican star defend his lightweight title (and thus his status as Ring Magazine world champion at 135 pounds) against the winner of the Michael Katsidis-Vicente Escobedo fight that takes place on the Mayweather-Marquez undercard.
If Marquez wins, however, the WBO will not strip him of his "super title" within their ranks, allowing him the option to look for another big money fight.
Katsidis and Escobedo meet for the interim WBO lightweight title in a fight that has the potential to steal the show on one of boxing's biggest cards of 2009. Both are coming off of good wins on April's Lightweight Lightning show.
There would almost surely be bigger and better fights for a losing Marquez (competitive or not) than the Katsidis-Escobedo winner, but he may want to come back with a fight of that level if he's unsuccessful, or even dominated by Mayweather.
This also gives Katsidis and Escobedo even more incentive; a win could well set them up with a shot at Marquez, who would be the biggest win of either's career by a long shot.