Slater signed a minor-league contract with the Rays on Tuesday, Robert Murray of FanSided.com reports.
Slater elected free agency Sunday after being DFA'd by the Mets, and he'll now have a chance to redeem himself in the Rays organization. The 33-year-old outfielder has slashed just .209/.286/.233 through 49 plate appearances in the majors this season, so he will likely need to show improvement at Triple-A Durham before the Rays give him another look in the big leagues.