ADVANCE FOR WEEKEND, JAN. 18-19 - FILE - In this May 15, 2006, file photo, Arizona Diamondbacks' Tony Clark starts his head-first slide to score on a hit by Johnny Estrada during a baseball game against the San Diego Padres in Phoenix. Clark has taken over as the head of the baseball players' union, following the death of Michael Weiner. (AP Photo/Roy Dabner, File)