White Sox pitcher Humber throws perfect game Sat Apr 21, 2012 7:02pm EDT (Reuters) - Chicago White Sox pitcher Philip Humber, a late-blooming top prospect who battled past elbow injuries, threw Major League Baseball's first perfect game in nearly two years on Saturday in a 4-0 win over the Mariners in Seattle. Humber struck out nine as he mowed down the Mariners lineup, retiring every one of the 27 batters he faced. The 29-year-old right-hander, who had won only 11 games over parts of seven seasons in the majors, threw only 97 pitches and needed no fielding heroics to register the perfect game. The last out came by an unusual strikeout, as pinch-hitter Brendan Ryan, with two strikes on him, failed to check his swing on an errant pitch and the umpire signaled strike three. But the ball bounced in the dirt and got past catcher A.J. Pierzynski. Ryan turned to argue with the umpire rather than make a dash for first base, and Pierzynski pounced on the ball and threw to first baseman Paul Konerko for the final put-out. That unleashed a wild celebration as White Sox players mobbed Humber, who ended up on the bottom of a big pile of players just off the mound. It was the 21st perfect game ever thrown in MLB and the first since the May 29, 2010, gem tossed by Roy Halladay of the Philadelphia Phillies.