[8][9] Pearson was assigned to the Rookie-level Gulf Coast League Blue Jays, and promoted to the Low–A Vancouver Canadians after making one start.

[10] In early September, Pearson was selected by Vancouver as the starter for the first game of their best-of-three Northwest League playoff series against the Spokane Indians.

[14] Pearson was assigned to the High–A Dunedin Blue Jays to begin the 2018 season, but opened the year on the disabled list with an oblique injury.

[15] He remained on the disabled list for the rest of the 2018 season, and played for the Surprise Saguaros of the Arizona Fall League during the offseason.

Pearson began 2019 with Dunedin, where he posted a 3–0 record, 0.86 ERA, and 35 strikeouts in 21 innings pitched before being promoted to the Double-A New Hampshire Fisher Cats in early May.

[20][21] With the 2020 Toronto Blue Jays, Pearson appeared in 5 games, compiling a 1–0 record with 6.00 ERA and 16 strikeouts in 18 innings pitched.

On July 27, 2024, the Blue Jays traded Pearson to the Chicago Cubs in exchange for Josh Rivera and Yohendrick Piñango.

[27][28] On September 4, Pearson pitched the 8th inning in a combined no-hitter (also featuring Shota Imanaga and Porter Hodge) against the Pittsburgh Pirates, the 4th of the season.