On May 12, 2009, Werth made a steal of home plate in a bases-loaded situation against the Los Angeles Dodgers, which came in the seventh inning after previously stealing both second and third base. Werth stole four bases in the game, leading the team to a 5–3 victory, and again tying a Phillies record. On June 27, Werth became the 14th player in Toronto's Rogers Centre history to hit a home run into the stadium's 500 level. On July 10, Werth was named to the NL All-Star Team as a replacement for New York Mets' outfielder Carlos Beltrán. On July 21, in a home game against the Chicago Cubs, Werth hit his first career walk-off home run, in the 13th inning against Jeff Samardzija, to deliver a 4–1 victory for the Phillies. He led the majors in pitches per plate appearance during the 2009 season, with 4.50. In Game 5 of the 2009 National League Championship Series, Werth hit home runs in the first and seventh innings, in a game which the Phillies won 10–4, clinching the series. Baseball fans voted Werth the 2009 "Unsung Star of the Year" in MLB's This Year in Baseball Awards.