Geoff Geary was drafted by Philadelphia Phillies in the 15th round of the amateur entry draft. He was awarded Red Barons Pitcher of the Year in after a stellar year in AAA. That year, he primarily filled three roles: as a starter, set-up man and closer, where he reached career-highs in games and saves and fell one win shy of tying his career high. He was awarded Phillies Minor League Pitcher of the Month for June 2003. He also was awarded the Greg Legg Tenth Man Award, by the Scranton booster club, given to a player who comes off the bench to consistently contribute to the success of their team. That year, he made his major league debut on August 27, 2003 against the Montreal Expos, allowing one run in his one inning of work. He appeared in only 5 games in 2003. In 58 innings in, he compiled a 3.72 ERA and showed improvement as the season went on by posting a 2.70 ERA after the all-star break. In, Geary went 7–1 with a 2.96 ERA in 91.1 innings and posted a career best ERA and a team best ERA for pitchers with over 25 innings pitched. He also had the lowest ERA in the National League for relievers with over 80 innings pitched. After making close to the major league minimum from 2003 to 2006, he became eligible for salary arbitrationfor the first time in the 2006– offseason and was offered $750,000 by the Phillies while he asked for $925,000. Geary agreed to a one-year contract worth $837,500 with the Philadelphia Phillies, avoiding arbitration. Geoff was pitching with the team's AAA affiliate the Ottawa Lynx until July 29, 2007 when the team recalled him after an injury to Ryan Madson.
Houston Astros
On November 7, 2007, Geary was traded to the Houston Astros along with Michael Bourn and Mike Costanzo for Brad Lidge and Eric Bruntlett. Geary had a career year in 2008 for the Astros with a career-low 2.53 ERA in 64 innings pitched. However, in 2009, Geary went 1–3 with an 8.10 ERA in 16 appearances before going on the disabled listMay 14 with tendinitis in his right biceps. On June 10, he was activated but placed on waivers and sent outright to Triple-A Round Rock Express. In October 2009 Geary was granted free agency.
On December 16, 2009, Geary signed a minor league contract with the Texas Rangers with an invitation to spring training. He played with the Oklahoma City RedHawks, where he appeared in 23 games and had a record of 4-5 with a 5.37 ERA when he was released on July 27, 2010.
On August 8, 2010, he signed a minor league deal with the Los Angeles Dodgers, and was assigned to Triple-A Albuquerque the following day. He appeared in eight games with a 5.06 ERA.
On February 16, 2011, he was signed to a minor league deal with the San Diego Padres. He was released on March 26.
After the MLB
After being released from the Padres, Geary signed a contract with the York Revolution of the Atlantic League on June 23, 2011. As of the 2011 Atlantic LeagueAll-Star Break, Geary had pitched 8 innings in 8 appearances and had a 4.50 ERA.
