Johnson was homeschooled and played his high school baseball for the Home School Texas Alliance for Christian Athletes. He was highly anticipated in the 2021 MLB Draft but was highly committed to attending Dallas Baptist University.
in his freshman season with DBU, he pitched both as a starter, and out of the bullpen. He made 18 appearances, 9 of them being starts. He had a 4.30 ERA with 47 strikeouts and 22 walks in 58.1 innings pitched. His opposing batting average was .257.
Last season as a sophomore, Johnson became a piece of the starting rotation, making 16 appearances with 15 starts. He held a 4.43 ERA with 116 strikeouts and 22 walks on the year which was good for an impressive 5.27 K/BB ratio. His opposing batting average was .239. This performance earned him a First Team All-Conference USA Selection along with a Third Team All-American selection from NCBWA.
Johnson is currently in his junior year with DBU and is expected to improve his numbers from last season as he develops.