He has previously played in Major League Baseball (MLB) for the Miami Marlins, Tampa Bay Rays, Milwaukee Brewers, Toronto Blue Jays, and Minnesota Twins.

[4] He spent 2016 with the Batavia Muckdogs and the Greensboro Grasshoppers, both in Single-A, posting a combined 2–3 record and 2.48 ERA in nine starts (11 appearances).

[5] In 2017, he was named the Marlins Minor League Pitcher of the Year after going 12–11 with a 2.53 ERA and 158 strikeouts in 27 games (25 starts) between the Advanced-A Jupiter Hammerheads and the Double-A Jacksonville Jumbo Shrimp.

[8] He pitched 4+1⁄3 innings, giving up eight hits and five runs (all earned) while striking out five and walking one; he took the loss, as the Marlins were defeated by the Boston Red Sox, 7–3.

[9] On April 25, facing Clayton Kershaw and the Los Angeles Dodgers, Richards pitched 4+2⁄3 innings, giving up one hit and striking out 10.

On July 31, 2019, Richards was traded to the Tampa Bay Rays (along with Nick Anderson) in exchange for Jesús Sánchez and Ryne Stanek.

[11] He made his first start as a Ray on August 18, 2019, against the Detroit Tigers, allowing two runs across three and a half innings in a 5–4 Tampa Bay victory.

On July 6, 2021, the Brewers traded Richards to the Toronto Blue Jays along with Bowden Francis in exchange for Rowdy Tellez.