On Opening Day, April 1, the St. Louis Cardinals played the 20,000th game in franchise history against the Arizona Diamondbacks, dating back to the start of their American Association (AA) play in 1882. Heading into the 2013 season, St. Louis had an all-time winning percentage of .518.
Early in the season, the Cardinals navigated around the loss of key players Chris Carpenter, Jason Motte, Rafael Furcal and Jaime García due to season-ending injuries. To offset these depletions, the St. Louis tapped heavily into their farm system. In a May game against the Colorado Rockies, rookie starting pitcher Shelby Miller set an all-time franchise record for a nine-inning game score of 98. Starter Adam Wainwright accumulated a franchise-record 34 2⁄3 innings (IP) before issuing his first walk on April 23 and earned NL Pitcher of the Month honors in June. First baseman Allen Craig produced the third-highest individual batting average with runners in scoring position at .454 as the Cardinals set an all-time Major League team record at .330. Rookie Matt Adams led the team in slugging percentage at .503. Second baseman Matt Carpenter, playing his first season at the position since turning professional, earned an All-Star selection as he led the Major Leagues in hits (199), runs scored (126), and doubles (55). In all, 20 rookies appeared in a game and the Cardinals collected 36 victories from their rookie pitchers. The 2013 edition set franchise records in fielding percentage (.988), pitching strikeouts (1254) and strikeouts per 9 innings pitched (7.73).
Holding off fierce competition from the Cincinnati Reds and Pittsburgh Pirates, the Cardinals clinched the division crown as each team won at least 90 games. The Cardinals finished the season with an NL-best 97–65 won–loss record. They opened the playoffs by defeating the Pirates in five games in the NL Division Series (NLDS). Advancing to their third straight National League Championship Series, they defeated the Los Angeles Dodgers in six games for their 19th NL pennant.
Rookie Michael Wacha, who had nearly no-hit the Washington Nationals late in September, continued his dominance throughout the postseason as he allowed no runs against the Dodgers in 13 IP, earning the NLCS MVP. It was the second straight NLCS appearance to which manager Mike Matheny guided the Cardinals, who became the first manager to appear in an LCS in his first two seasons. Rookie closer Trevor Rosenthal extended a 20-inning postseason scoreless streak that started in the 2012 NLDS. The Cardinals met the Boston Red Sox in the World Series, only to lose the series in six games.