The Rays designated Slater for assignment Friday, Marc Topkin of the Tampa Bay Times reports.
The veteran outfielder joined Tampa Bay on a minor-league deal in late May and was added to the big-league roster June 8. Slater went 6-for-22 with three walks, two doubles, three steals, an RBI and two runs in seven games for the Rays, but he'll be the odd man out after the club activated Jonny DeLuca (hamstring) from the injured list. Slater has already seen action with three MLB clubs in 2026 and could return to free agency if he passes through waivers unclaimed.