Geer is a 2002 graduate of Forney High School. He was a four-year starter and letterman for the Jackrabbits under coaches Ronnie Ortegon and Sam Gillispie. Geer earned all-District 13-3A honors as a freshman and also helped his team to the district championship and to the state tournament two years in a row. He was also a starter and letterman for the football team. On the academics side he posted a 4.3 grade point average on a 5.0 scale.
Geer went 4–2 with a 3.96 ERA in 12 games, 11 starts, for the Low-A Eugene Emeralds and the Single-A Fort Wayne Wizards in 2005. He won three straight games with the Emeralds from July 24 to August 4, allowing six runs over 191⁄3 innings. He was promoted to Fort Wayne on August 8 and allowed three runs, two earned, over six innings to win his Wizards' debut the next night.
In 2006 Geer posted a 13–6 record and a 4.12 ERA in 27 games, 26 starts, between Single-A Fort Wayne and the High-A Lake Elsinore Storm. He led the organization in wins. Geer tossed 22 scoreless innings in his last three starts with the Wizards before being promoted to Lake Elsinore on June 17. After losing his first three starts with the Storm, went 7–1 in 12 starts from July 8 to September 4.
Geer held left-handed batters to a .146 mark. He tossed at least 5 innings and yielded two runs or less in each of his Big League outings. His contract purchased from the Triple-A Portland Beavers on August 29. Geer made his major league debut for the Padres on August 30, 2008 with a win over the Colorado Rockies. He suffered first Big League loss on September 17 against Colorado despite throwing five innings of one-run ball with five strikeouts, as San Diego fell 1–0. With Portland he went 8–9 with a 4.54 ERA, 107 strikeouts and 45 walks in 28 appearances, 27 starts. He led the Pacific Coast League in innings pitched while tied for third in starts. His starts also tied for the team lead behind Cesar Ramos. Geer tied for the most starts in one season by a Portland pitcher since the team returned to the PCL in 2001 sharing the record with Junior Herndon in '01 and Dennis Tankersley in 2003.
In 2009 Geer split the season between Portland and San Diego. With Portland he went 2–5 with a 4.44 ERA in 522⁄3 innings pitched in nine games, all starts, including one complete game. With the Padres he went 1–7 with a 5.96 ERA in 19 games, 17 for starts. On October 13 Geer was removed from the 40-man roster and sent outright to Triple-A Portland.[3]
Geer spent the entire 2010 season with Portland, where he went 11–11 with an ERA of 5.41. He missed most of the 2011 season while recovering from stage III melanoma, appearing in just two games for the Triple-A Tucson Padres before undergoing surgery to remove lymph nodes from his neck. He then went on to pitch in the Arizona Fall League.[4]
Geer returned to action in 2012, pitching in 28 games between Double-A and Triple-A, going 7–10 with a 5.29 ERA. In 2013, he pitched in 35 games, 12 of them starts. He finished 8-6 and a 3.54 ERA, his lowest since 2007.
On February 14, 2014, Geer re-signed with the Padres organization on a minor league contract.[5]
