By Sean McDaniel: Challenger Marco Antonio Rubio (53-5-1, 46 KO’s) could be the one to end WBC middleweight champion Julio Cesar Chavez Jr’s run as the champion by beating him and taking his title on Saturday night at the Alamodome in San Antonio, Texas.

Rubio would be doing former WBC middleweight champion Sergio Martinez a big favor if he does beat Chavez Jr. because Chavez Jr. and his promoter Bob Arum have been slow in giving Martinez a shot at the title even after the WBC ordered Chavez Jr. to fight Martinez.

Rubio, 31, may find it difficult to beat Chavez Jr. because he’s a well-schooled boxer/puncher and has a learned a lot from his famous father Julio Cesar Chavez, as well as from his trainer Freddie Roach. Chavez Jr. didn’t have the benefit of an amateur background, and instead has used the pro game to develop his skills slowly over the past eight years.

You can still make an argument that Chavez Jr. is still developing his game because he’s clearly kept away from Martinez and we’re not seeing Chavez Jr. being matched against the best of the middleweights like Dmitriy Pirog, Gennady Golovkin, Felix Sturm, Matthew Macklin and Andy Lee. Chavez Jr. can do pretty much the same things that WBC junior middleweight champion Saul Alvarez can do at junior middleweight. The difference between them is that Alvarez doesn’t come into his fights with a hulking physique like Chavez Jr. and doesn’t outweigh his opponents by 20 to 30 pounds like Chavez Jr. has been doing recently.

Rubio may have to do a little extra to get a decision in this fight. Chavez Jr. is the name fighter, and you can imagine that the much less popular Rubio may need to really dominate this fight if he wants to get a decision win. It could take a knockout for Rubio to win, and that might prove tough because facing a guy that outweighs you by as much as 30lbs will be tough. He’ll have the speed advantage but hitting someone that much bigger than you is going to be a problem.