The Rays have released reliever Mark Lowe at his request, reports ESPN.com's Jerry Crasnick (via Twitter). He had an opt-out clause that could be exercised this coming Friday.
Lowe, 30, had a strong spring for the Rays, allowing just one earned run in 10 1/3 innings while striking out 12 and walking just one batter. Of course, he struggled mightily in eleven MLB appearances last year for the Angels, issuing 8.5 free passes per nine against just 5.4 K/9.