Matthew Macklin v Julio Cesar Chavez Jr in Las Vegas next April? http://www.irish-boxing.com/2012/11/matthew-macklin-v-julio-cesar-chavez-jr-next-april/
There's no evidence that this fight will be made or is even really in talks. The fact that Macklin thinks it could take place in Vegas indicates he has no information on the subject since Chavez likely won't be able to even fight there in April and it sounds more like he's merely wishing he gets the fight..
People misinterpreted the press release which said it was someone who lasted 11 rounds with Martinez. It's referring to someone who fought Martinez 7 years ago at 154, not Matthew Macklin.