By Dan Ambrose: The June 4th card at the Staples Center in Los Angeles, Calfornia has two good fights on the card between unbeaten Julio Cesar Chavez Jr. (42-0-1, 30 KO’s) facing WBC middleweight champion Sebastian Zbik (30-0, 10 KO’s) and undefeated junior middleweight contender Vanes Martirosyan (29-0, 18 KO’s0 going up against the tough Saul Roman (34-8, 29 KO’s) in a fight for the vacant World Boxing Council (WBC) Silver junior middleweight title in 12 rounds of action.

The Chavez Jr. vs. Zbik fight will be the main event, but the Martirosyan-Roman fight could steal the show if Martirosyan decides to turn up the heat and look to be more offensive against him.

Chavez Jr. and Martirosyan battled it out at the media day recently, sparring six hard rounds in front of boxing fans. Chavez Jr. is in very good shape and appears to have packed on the muscle for this fight. He’s lost his baby fat and looks to be a lot more powerful than he’s looked in previous fights. Whether his conditioning will translate to a better performance is the real test. Chavez Jr. looked fat, slow and weak in his last fight against Billy Lyell in January.

It seems like everyone jumped on Chavez’s case because of how poor he looked in the Lyell fight. Chavez Jr. brought good ratings for the fight on cable, but wasn’t able to turn that into an impressive performance. Chavez Jr. has clearly worked his tail off to get in the kind of condition that he is in now with only two weeks to go before the Zbik fight. However, it’s now up to Chavez Jr. to show that he can put in a good performance in the ring. He looked good in beating fringe contender John Duddy last year in June, but that Duddy, a fighter that had never really done much beyond the B level in his career.