Manager Nacho Beristain told the Mexican media that IBF bantamweight champion Rafael Marquez has his next bout scheduled for April 7 in Las Vegas.  An opponent has not been selected yet, but Beristain mentioned three names: Genaro Garcia (Boxingtalk #3), Mauricio Martinez (Boxingtalk #11) and Pete Frissina.  The last name seems implausible because Frissina has not fought since Marquez overwhelmed him in two rounds over a year ago.  Marquez (Boxingtalk #1) is 33-3 and has won five straight title bouts.  --Scott Shaffer