In 2005, he led the White Sox to their first American League pennant since 1959, and their first World Series win since 1917 with a 4-game sweep of the Houston Astros. Guillén claimed that he might retire after the 2005 season should the White Sox win the World Series, but at the parade celebrating the World Champions he received cheers from the fans when he announced he would indeed return to manage the next season. The White Sox picked up the 2006 option on his contract, added two more years and included an option for the 2009 season. In November, Guillén was voted the 2005 American League Manager of the Year Award by the Baseball Writers' Association of America.