Atlanta recalled Mederos from Triple-A Gwinnett on Wednesday.
Atlanta is swapping in Mederos for Connor Thomas, who was optioned to Triple-A after covering 3.2 innings out of the bullpen in Tuesday's loss to the Pirates. Mederos made one two-inning scoreless appearance for Atlanta earlier this season and holds a 5.40 ERA and 39:22 K:BB over 43.1 frames at the Triple-A level in 2026.