The Rays designated Wisler for assignment Monday, Tricia Whitaker of Bally Sports Sun reports.
Wisler was activated from the 15-day injured list Thursday following a one month absence with a neck strain, but he will no longer have a spot on the Rays' 40-man roster after being DFA'd Monday. The reliever has produced a 2.25 ERA and 1.00 WHIP with 35 strikeouts over 44 innings in 39 appearances with Tampa Bay this season. Wisler could get claimed off waivers by a contender in need of an additional bullpen arm.