In the midst of the 2002 trade deadline he was traded to the Florida Marlins. His statistics for the season drastically improved after the trade. The following season, he was again a key part in helping the inexperienced Marlins win the 2003 World Series. In Game 6 of the NLCS, the Marlins were five outs away from being eliminated when Cubs fan, Steve Bartman, prevented a foul ball from being potentially caught by extending his arms over Moisés Alou while Alou attempted to field the pop-up. Mordecai's subsequent three-run double blew the game open, highlighting the Cubs' historic collapse in what is sometimes referred to as simply "The Inning". Mordecai would go on to win his second World Series, as the Marlins handily defeated the Yankees in the World Series.