He split the 2017 season between the Low-A Hudson Valley Renegades and the Single-A Bowling Green Hot Rods, posting a 2.27 ERA with 29 strikeouts in 31.2 innings pitched across 20 appearances.

[9] At that point, in lieu of playing baseball which he felt was not going to work out, and uncertain as to what he would do with his future, the 23-year-old Long took EMT classes during the summer, thinking perhaps he would become a firefighter.

[10] After not playing for a team in 2018, Long signed a minor league contract with the Chicago White Sox organization on March 5, 2019.

[12] He spent the 2019 season in Single-A with the Kannapolis Intimidators, pitching to an 8–5 record and 3.06 ERA with 112 strikeouts and a WHIP of 1.041 in 97.0 innings of work.

[13] He held batters to a .205 batting average, with 10.4 strikeouts and 2.6 walks per nine innings, and his fastball hit 95 mph.

[16] On November 17, 2020, Long signed a minor league contract with the San Francisco Giants organization that included an invitation to spring training.

[17][11][18] He was assigned to the Double-A Richmond Flying Squirrels to start the 2021 season, later receiving a promotion to the Triple-A Sacramento River Cats, where he logged 7.2 scoreless innings.

[11] On June 7, 2021, it was announced that Long would be promoted to the major leagues for the first time during the following series, to be the starting pitcher against the Texas Rangers.

Long notched his first MLB strikeout in the game, punching out Rangers infielder Nick Solak, and struck out seven of the first ten batters he faced.

Pitching for three minor league teams: Triple-A Sacramento, Double-A Richmond, and the Single-A San Jose Giants, he was 1–1 with a 2.34 ERA in 42.1 innings over 16 games (7 starts).

[26] On July 6, Long recorded his first save against the Arizona Diamondbacks, striking out Jordan Luplow on three pitched as his only batter faced.

[35] In 16 games for the Triple–A Omaha Storm Chasers, he recorded a 1.31 ERA with 23 strikeouts and two saves across 20+2⁄3 innings pitched.