When Mark Munoz got injured it forced Michael Bisping into a match with Chael Sonnen and left Demian Maia without an opponent for the UFC on Fox 2 card. The immediate demand from fans was for the UFC to move Rousimar Palhares (who scored a quick win at UFC 142) into a fight with Maia. It turns out that Palhares turned down the short-notice no-rest fight (at least according to Dana White on Twitter) and the promotion settled on giving the fight to Chris Weidman.
For his part, Maia says that he didn't want to fight Palhares. Not because he was afraid, but because he thinks that Brazilian middleweights shouldn't face each other. Via SporTV (translated by Tom Mendes):
"It was rumored (a fight with Palhares), but I thought there would not be any possibilities (of it happening), because he just fought, it doesn't make sense for him to throw himself into another fight right now. "Toquinho" trained a few months for this fight. Just because it was fast doesn't mean there were no wear and tears. But I don't even think about that. To be honest, the Brazilian fans should be more worried about seeing us fighting foreigners. There are (only) a few Brazilian fighters in the division and I think that, aside of the title, since it's Anderson who is the champion, the Brazilians should not face each other."