The Rays reassigned Kolarek to their minor-league camp Sunday.
Kolarek reached the big leagues in 2017 and appeared in 12 games for the Rays, logging a 6.48 ERA and 1.56 WHIP in 8.1 innings. Things went better this spring for the lefty, who tossed four scoreless frames, but Tampa Bay didn't have a need for an extra southpaw in the bullpen with Jose Alvarado and Dan Jennings in the fold.