Leasher was drafted by the San Diego Padres in the 6th round, with the 168th overall selection, of the 2017 Major League Baseball draft.[1] He split his first professional season between the rookie-level Arizona League Padres and Low-A Tri-City Dust Devils, posting a 4.29 ERA over 11 starts. Leasher spent 2018 with the Single-A Fort Wayne TinCaps and High-A Lake Elsinore Storm. In 24 appearances (18 starts) split between the two affiliates, he compiled an aggregate 6-7 record and 3.49 ERA with 117 strikeouts across 118+2⁄3 innings pitched.[2]
Leasher split the 2019 campaign between Lake Elsinore and the Double-A Amarillo Sod Poodles, registering a combined 10-8 record and 3.60 ERA with 114 strikeouts in 122+1⁄3 innings pitched over 23 games (19 starts). He did not play in a game in 2020 due to the cancellation of the minor league season because of the COVID-19 pandemic.[3] Leasher returned to action in 2021 with the Double-A San Antonio Missions and Triple-A El Paso Chihuahuas. In 16 games (15 starts) for the two affiliates, he logged a 4-5 record and 3.76 ERA with 62 strikeouts across 64+2⁄3 innings pitched.[4]
Leasher returned to El Paso for the 2022 season, making 35 appearances (11 starts) for the team, in which he posted an 8-6 record and 4.23 ERA with 91 strikeouts across 87+1⁄3 innings pitched.[5] He split the 2023 campaign between San Antonio and El Paso, accumulating a 3-3 record and 5.37 ERA with 51 strikeouts across 29 games (9 starts). Leasher elected free agency following the season on November 6, 2023.[6]
On July 16, 2024, Leasher signed with the Fubon Guardians of the Chinese Professional Baseball League.[9] In 9 starts for Fubon, Leasher compiled a 4-3 record and 2.21 ERA with 45 strikeouts across 53 innings of work.
Wei Chuan Dragons
On March 14, 2025, Leasher signed with the Wei Chuan Dragons of the Chinese Professional Baseball League.[10][11] He made 24 appearances for the Dragons, accumulating an 0-2 record and 3.25 ERA with 28 strikeouts across 27+2⁄3 innings pitched. Leasher was released by Wei Chuan on August 29.[12]
