LAWRENCEVILLE — Former Atlanta manager Bobby Cox returned Tuesday night to skipper the Braves' top prospects in a 4-3 rain-shortened exhibition loss to the major league club. Cox wore a uniform for the first time since retiring in 2010 with the fourth-most victories (2,504) in baseball history.Michael Bourn, Martin Prado and Brian McCann each drove in a run during the fifth inning to help the big leaguers rally for the victory. The Braves open the season at the New York Mets on Thursday.