While not considered a remarkable hitter in the Pirates organization, Gushue demonstrated an immediate power surge in the Nationals organization, where he started 2017 with the High–A Potomac Nationals.[6][7] He was named a Carolina League All-Star, alongside teammates Víctor Robles and Kelvin Gutiérrez.[8] Midseason prospect rankings produced by MLB Pipeline saw Gushue vault into the Nationals' top 30 prospects, ranking as their third-best catching prospect behind Raudy Read and Pedro Severino and coming in at 25th overall among Washington prospects.[9] Gushue led the Potomac Nationals in home runs with 18 on the season along with slashing .241/.327/.437 with 67 RBI.[10] He finished the season with the Double–A Harrisburg Senators, playing four games with them.[11] He went on to play for 13 games for the Mesa Solar Sox in the Arizona Fall League after the season.[12]
Gushue did not play in a game in 2020 due to the cancellation of the minor league season because of the COVID-19 pandemic.[16] On November 2, 2020, he elected free agency.[17]
Chicago Cubs
On November 16, 2020, Gushue signed a minor league contract with the Chicago Cubs organization.[18] He was assigned to the Triple-A Iowa Cubs to begin the 2021 season, where he slashed .272/.328/.440 with 5 home runs and 27 RBI in 36 games. On June 30, 2021, Gushue was selected to the 40-man roster and promoted to the major leagues for the first time following an injury to José Lobatón.[19] He made his MLB debut that day as an injury replacement for Patrick Wisdom. Gushue went 0-4 in 2 games with Chicago before he was designated for assignment on July 5.[20] He was outrighted to Iowa on July 8.[21] Gushue became a free agent following the 2021 season.
Washington Nationals (second stint)
On February 10, 2022, Gushue signed a minor league contract to return to the Washington Nationals.[22] He elected free agency on November 10, 2022.