Johnson has been diagnosed with a torn ACL and LCL in his left knee and will undergo season-ending surgery, Colin Beazley of the Pittsburgh Post-Gazette reports.
Johnson had to be carted off the field during this past Saturday's game with Triple-A Indianapolis after stumbling over the first-base bag while attempting to leg out an infield single. It's a brutal injury for the 22-year-old infielder, who will undergo more examinations before undergoing surgery, with an eye toward being back on the field during the 2027 season. Johnson had a .651 OPS with 24 steals (in 30 attempts), eight home runs and 37 RBI across 401 plate appearances in Triple-A this season before the injury.