Lemoine attended Bridge City High School in Bridge City, Texas.[1] He was drafted in the 21st round, 666th overall, of the 2012 MLB draft by the Texas Rangers but did not sign.[2] He attended the University of Houston for three years (2013–2015), playing college baseball for the Cougars.[3] He played for the 2014 USA Baseball Collegiate National Team, going 2–2 with a 2.45 ERA in 18+1⁄3 innings for them.[4][3] During his junior year of 2015, he suffered a right shoulder injury that limited him to just 5 games that season.[3]
On January 8, 2022, Lemoine signed a minor league contract with the Oakland Athletics.[11] On April 7, the Athletics selected Lemoine's contract, adding him to their opening day roster.[12] He made 9 appearances for Oakland, working to a 7.71 ERA with 13 strikeouts in 16+1⁄3 innings pitched. Lemoine was designated for assignment on July 12. He cleared waivers and was sent outright to the Triple-A Las Vegas Aviators on July 16.[13] Lemoine spent the remainder of the year in Triple-A, posting a 2–1 record and 4.95 ERA with 26 strikeouts in 36+1⁄3 innings of work. He elected free agency following the season on November 10.[14]
Lancaster Barnstormers
On April 12, 2023, Lemoine signed with the Lancaster Barnstormers of the Atlantic League of Professional Baseball.[15] In 6 starts for Lancaster, he posted a 1–3 record and 5.57 ERA with 19 strikeouts in 32+1⁄3 innings pitched. With Lancaster, Lemoine won the Atlantic League championship.[16]
Lemoine retired from professional baseball following the 2023 season.[17]