By Rick Reeno

Former two division world champion Sergio Martinez (49-2-2, 28KOs) is not denying his deep dislike for Mexican superstar Julio Cesar Chavez Jr. (46-0-1, 32KOs). On Saturday night at the Thomas & Mack Center in Las Vegas, Martinez will challenge Chavez for the WBC middleweight crown.

Despite the months of trash talking, Martinez reveals that only recently did his problem with Chavez "become personal." Apparently, Chavez made a comment during an episode of HBO's 24/7 reality series, and it hit a nerve with Martinez.

"He said something at the end of one of the 24/7s. He said to 'respect the sport' - to me. And I don't know anybody else who doesn't respect the sport like Chavez doesn't respect it. That comment made it personal," Martinez said.

When he was asked to explain his reasons for accusing Chavez of disrespecting the sport of boxing - Martinez fired off in a fury.

"I say what everybody thinks. He doesn't respect the sport. I'm getting upset [talking about this]. Where do I start. He always has a problem with his weight. Two weeks before the fight with Marco Antonio Rubio, he committed an infraction with driving under the influence. He has a problem with anti-doping, with the positive result in Nevada," Martinez said.

"Nobody knows what happened with the anti-doping [tests] against Rubio and Andy Lee. One of the best trainers in the world, Freddie Roach, he makes him wait and doesn't show up to the gym [to train]. He insults our sport."