The Padres released Mercado on Thursday.
Mercado lost his spot on Triple-A El Paso's roster after the affiliate needed to clear room for outfielder Brandon Lockridge, whom the Padres acquired in a trade with the Yankees on Tuesday. The 29-year-old Mercado played in 20 games at the big-league level with St. Louis in 2023 but never received a call-up to San Diego after slashing .226/.307/.425 with 11 home runs and 12 stolen bases across his 307 plate appearances with El Paso.