Star Chicago Cubs slugger, Sammy Sosa has backed out of playing in the All Stars Game because of problems in his left shoulder. Sosa, who established a new Major League mark of 20 home runs in a month last month, said he slept in a bad position and hurt his shoulder. For the same reason, Sosa did not play with the Cubs on Sunday, and expects to not play on Monday. "The doctor said it would take three to four days to recover," he said, explaining. Second baseman Bret Boone of the Cincinnati Reds will replace Sosa on the roster of the National League. Sosa said he would be present at the game. "I will be watching McGwire," he said. He said that it was better that it happened now, half point through the season, when he could rest three days and be back on Thursday for a "strong finish." Sosa has batted 33 home runs, and has 81 runs batted in, and a .324 average this season.