Sentence:  Shea , the chairman of Mayor Wagner 's Baseball Committee , will be joined on the dais by Warren Spahn , the <WSD>southpaw</WSD> pitching ace of the Milwaukee Braves ; Frank Graham , the Journal-American sports columnist ; Bill Mazeroski , the World Series hero of the Pittsburgh Pirates , and Casey Stengel , the former manager of the Yankees . 
Meaning of the word marked with <WSD> tags:  a baseball pitcher who throws the ball with the left hand