12. Gary Sheffield, Milwaukee Brewers/Atlanta Braves/L.A. Dodgers/New York Yankees/San Diego Padres/Florida Marlins/Detroit Tigers
Yankees/San Diego Padres/Florida Marlins/Detroit Tigers What's most terrifying about Shef isn't his wrist-whippingly feral swing, which sends barely foul liners careening at his poor third-base coach. No, it's that he clearly doesn't give a shit about anything not relating to his contract status. A new position in the middle of a pennant race? No problem. A sex tape allegedly depicting his wife doing some decidedly non-Christian stuff with R. Kelly? Pshaw. On the most rational of days, his eyes flash mad crazy.