2004 Houston Astros season

The 2004 Houston Astros season was the 43rd season for the Major League Baseball (MLB) franchise located in Houston, Texas, their 40th as the Astros, 43rd in the National League (NL), 11th in the NL Central division, and fifth at Minute Maid Park. The Astros entered the season with an 87–75 record, in second place and one game behind the division-champion Chicago Cubs. In the NL Wild Card race, the Astros also finished second, four games behind the World Series-champion Florida Marlins.

On April 5, pitcher Roy Oswalt made his second Opening Day starts for the Astros, who hosted the San Francisco Giants, but were defeated, 5–4. On May 6, Roger Clemens moved into second place all-time in strikeouts, increasing his total to 4,140, while on May 8, Craig Biggio became the first Astro to reach 2,500 career hits.

The Astros hosted the MLB All-Star Game at Minute Maid Park, which was the first held in Houston since 1986. Outfielders Carlos Beltrán and Lance Berkman, second baseman Jeff Kent, and Clemens each represented the Astros as All-Stars, and Clemens was selected as the starting pitcher for the National League.

Having limped into the All-Star break with a 44–44 record, Phil Garner was named manager, the 16th in franchise history, replacing Jimy Williams. On September 18, Jeff Bagwell scored both the 1,500th run and run batted in (RBI) of his career to become the 29th major leaguer and first Astro to reach both milestones. Kent hit his 300th home run on September 29. The Astros won 36 of their final 46 games: 36–10 (.783).

Having completed the regular season with a 92–70 record, Houston ranked second in the NL Central, finishing 13 games behind the division-champion St. Louis Cardinals. However, the Astros captured the NL Wild Card title for the first time, finishing just one game ahead of the San Francisco Giants. It was the eighth playoff qualification overall for Houston.

In the National League Division Series (NLDS), the Astros defeated the Atlanta Braves 3-games-to-2 by scoring an NLDS-record 36 runs. Hence, the Astros won a playoff series for the first time in franchise history, while also defeating Atlanta in a playoff series on their fourth attempt. They advanced to the third National League Championship Series (NLCS) in franchise history and first since 1986 to face the Cardinals. Beltrán, who connected for eight home runs between the NLDS and NLCS, tied Barry Bonds' record for one postseason in 2002. However, the Astros were eliminated in 7 games, ending their season as St. Louis claimed the NL pennant.

Clemens won the NL Cy Young Award, becoming the fourth pitcher to win the award in both leagues, the only one with seven overall, and joined Mike Scott in 1986 as the second Astro to be selected.