He started the 2013 with the Triple-A Tucson Padres but was demoted to Double-A San Antonio Missions after posting an 8.03 ERA.

On December 17, 2016, Sampson signed a minor league contract with the Arizona Diamondbacks that included an invitation to spring training.

On January 5, 2019, Sampson signed a minor league contract with the San Francisco Giants organization.

[14] In 6 games (5 starts) split between the rookie–level Arizona League Giants and Double–A Richmond Flying Squirrels, he posted a 1–3 record and 5.09 ERA with 18 strikeouts across 17+2⁄3 innings pitched.

[16] Sampson posted a 6.43 ERA in 8 appearances between the Low-A Kannapolis Cannon Ballers and the Triple-A Charlotte Knights before he was released on July 20.

In 2023, Sampson made 21 appearances (19 starts) for the team and posted an 8–5 record and 3.11 ERA with 115 strikeouts across 110.0 innings pitched.

[22] On July 24, 2024, Sampson signed with the Charleston Dirty Birds of the Atlantic League of Professional Baseball.