He played in Major League Baseball (MLB) for the Houston Astros, Arizona Diamondbacks, Tampa Bay Rays, San Diego Padres, Philadelphia Phillies, New York Yankees, Pittsburgh Pirates, Miami Marlins, and Colorado Rockies.

[4] He began his career as a starting pitcher with the Michigan Battle Cats of the Class A Midwest League during the 2001 season.

Qualls joined with Dan Wheeler and Brad Lidge to form a strong bullpen, as the Astros reached the 2005 World Series.

[6] On December 14, 2007, the Astros traded Qualls to the Arizona Diamondbacks, along with Chris Burke and Juan Gutiérrez, for José Valverde.

[17] On Friday, January 25, 2013, Chad Qualls reportedly agreed to a minor league deal with the Miami Marlins.

[18] Following a game on Tuesday, July 30, 2013, between the Marlins and Mets, Qualls became an overnight social media viral sensation.

Qualls punctuated his scoreless 7th inning stint in which he walked one, allowed one hit, and struck out two, with an attempted fist pump as he ran towards the dugout.

Leaving the mound after strike-three against the Mets' Omar Quintanilla, Qualls punched the air in celebration as he headed toward the dugout.

Qualls was uninjured and bounced up quickly and continued to the dugout, where he covered his face in a towel and laughed with teammates.

His return to the team marked the first time an Astro played two separate stints as both a National and an American League franchise.

Qualls throws two main pitches: a heavy sinker in the low-to-mid 90s, and a hard slider in the mid-to-upper 80s.