Richardson made his MLB debut with 1+1⁄3 innings of scoreless relief against the Toronto Blue Jays on September 28, 2009.

Richardson made 26 appearances for Boston during the 2010 season, recording a 4.15 ERA with 12 strikeouts across 13 innings of work.

[6] On June 8, 2012, Richardson signed with the Sugar Land Skeeters of the Atlantic League of Professional Baseball.

He pitched in 14 games in 2015 (with four starts) combined for the Double–A Tulsa Drillers and Triple–A Oklahoma City Dodgers and was 2–0 with a 2.08 ERA and 25 strikeouts.

In 8 games split between Tulsa and Oklahoma City, he struggled to a 6.48 ERA with 12 strikeouts across 8+1⁄3 innings pitched.

[9] On June 15, 2016, Richardson signed with the Long Island Ducks of the Atlantic League of Professional Baseball.

On April 13, 2017, Richardson signed with the Sugar Land Skeeters of the Atlantic League of Professional Baseball.

On September 8, 2017, Richardson signed with the Long Island Ducks of the Atlantic League of Professional Baseball.

On July 4, 2023, Richardson signed with the Toronto Maple Leafs of the Intercounty Baseball League (IBL).

[12] As part of the television show Knight School, Richardson tried out for the Texas Tech Red Raiders men's basketball team.