Martinez to undergo surgery

Sergio Martinez is set to go under the knife next week to rectify a minor tear sustained in his knee tissue during his WBC middleweight title victory over Julio Cesar Chavez Jnr on Saturday night.

The Argentine southpaw defeated Chavez on points over 12 rounds but also injured his left hand in the fight and is now wearing a sort cast.

"He has some kind of tear in his knee," promoter Lou DiBella told ESPN. "It's not severe or an immense injury, thankfully.

"The hand is broken. His left hand is in a soft cast. It's a hairline fracture. There is also a bad bruise as well as the hairline fracture. That shouldn't be a big problem. The hand turned out to be better than we thought it was."

After the fight at the weekend, Chavez failed a drugs test for marijuana.