[3] The Pittsburgh Pirates selected Brubaker in the sixth round of the 2015 Major League Baseball draft.

[11] He returned to Indianapolis to begin 2019, but appeared in only six games during the season due to a strained forearm.

[15] In 2022, Brubaker made 28 starts for Pittsburgh, logging a 3–12 record and 4.69 ERA with 147 strikeouts in 144 innings pitched.

On January 13, 2023, Brubaker agreed to a one-year, $2.275 million contract with the Pirates, avoiding salary arbitration.

[19] On March 29, 2024, the Pirates traded Brubaker and international signing bonus pool space to the New York Yankees in exchange for a player to be named later.