A pair of potentially explosive match-ups will be shown during SHOWTIME’s Free Preview Weekend when two-time time World Boxing Council (WBC) Champion Jose Luis Castillo takes on former International Boxing Federation (IBF) titleholder Julio “The Kidd’’ Diaz and undefeated Jeff Lacy risks his IBF super middleweight crown against once-beaten Rubin “Mr. Hollywood’’ Williams on SHOWTIME CHAMPIONSHIP BOXING Saturday, March 5. The world championship doubleheader, which will be co-promoted by Top-Rank, Inc., and Gary Shaw Productions, LLC, will take place at Mandalay Bay Resort & Casino in Las Vegas and start at 10:30 p.m. ET/PT (delayed on the West Coast). [details]