He has played in Major League Baseball (MLB) for the Minnesota Twins, Colorado Rockies, Philadelphia Phillies, and Cleveland Indians.

At Ronald Reagan High School in San Antonio, he was an All-American with a 22–2 record and 0.65 earned run average his final two seasons (2002 and 2003) with four no-hitters (one perfect game), and a 7.9 strikeout-to-walk ratio.

In Manship's first season of professional ball (2006), his combined effort for the Gulf Coast League Twins and Fort Myers Miracle was 22 strikeouts in 15 innings pitched with only two earned runs for a 1.20 ERA.

Manship began the 2009 season at New Britain, going 6–4, with a 4.28 ERA and 45 strikeouts in 13 starts, before being promoted to the triple A Rochester Red Wings on June 24.

On August 12, 2009, Manship had his contract purchased by the Twins when left-handed pitcher Glen Perkins was placed on the disabled list with a shoulder strain.

Manship began the 2010 season with the Rochester Red Wings, posing a 2–2 record with a 3.48 ERA and 13 strikeouts in four April starts.

He was called up to pitch for the Twins on May 1, starting in place of the unavailable Nick Blackburn, who was not with the team for family reasons.

On December 5, 2013, Manship signed a minor-league contract with the Philadelphia Phillies that includes an invitation to spring training.

The Indians declined to tender Manship a contract for the 2017 season by the December 2, 2016 deadline, making him a free agent.