He played college baseball for the Vanderbilt Commodores and was selected by the Rangers with the second overall pick of the 2021 MLB draft.

[5] Leiter was considered a top prospect for the 2019 Major League Baseball draft, but due to his strong commitment to Vanderbilt University, was not selected until the 20th round by the New York Yankees, but did not sign.

[11][12] In his college debut on February 18, 2020, Leiter pitched five no-hit innings while striking out 12, leading Vanderbilt to a 3–0 victory over the University of South Alabama.

[30][31] Leiter attended an organization draftee orientation at the Rangers spring training complex after signing, but did not appear in a professional game in 2021, instead choosing to return to Vanderbilt to continue college course work.

[37] He received a non-roster invitation to major league spring training in 2023,[38] and returned to Frisco to open the season.

[41] He finished the 2023 season with one start for the Round Rock Express of the Triple-A Pacific Coast League.

[44] On April 18, 2024, the Texas Rangers selected Leiter’s contract and promoted him to make his major league debut that day against the Detroit Tigers.