Atlanta designated Kimbrel for assignment Saturday.
Kimbrel was called up from the minors Friday for a return to the big-league club that drafted him in 2008, but the reunion may end up being short-lived. The veteran reliever looked fine in pitching a scoreless inning against the Giants on Friday, though he allowed a hit and a walk while striking out one batter and averaging only 91.5 mph on his fastball. Atlanta filled Kimbrel's bullpen spot by recalling lefty reliever Austin Cox from the minors.