By Ernesto Castellanos, notifight.com

Las Vegas, Nevada - WBA/WBO lightweight champion Juan Manuel Marquez has said that a loss to Australian Michael Katsidis would be "catastrophic" to his career at this point in time. Marquez defends his titles later tonight at the MGM Grand. A lot of big fights are riding on a victory, including a third fight with Manny Pacquiao and a huge all-Mexican showdown with Erik Morales.

"I can not afford to lose. To me it would be catastrophic to suffer a loss at this point, just as I'm in the hunt for big fights and big purses. I would lose a possible fight with Manny Pacquiao, who may face me, and I could lose an opportunity to face Erik "El Terrible" Morales, a fight that is growing in demand," Marquez said.   "Katsidis is a real opponent, strong, combative and always going forward. We're going to give it our best shot."

Éric Gómez, head matchmaker for Golden Boy, agrees that Marquez's career is at stake in this fight:

"There are many plans for Marquez, but first he has to win [tonight]," Gomez said.