The Cardinals selected Baez's contract from Double-A Springfield on Tuesday, John Denton of MLB.com reports.
Baez adjusted well to Double-A ball upon receiving his promotion in late May, slashing .271/.371/.509 with 16 homers, 55 RBI, 46 runs scored and 33 stolen bases across 79 games at Springfield. His breakout season has earned him a spot on St. Louis' 40-man roster ahead of the Rule 5 Draft in December, and he may be a candidate to make his big-league debut in 2026 if he continues to stuff the stat sheet in the minors.