Phillips is a free agent, but he already had that right with six years in the minors and having been designated previously.
The Orioles outrighted Phillips, outfielder Lew Ford and infielder Steve Tolleson on Friday to create room on their 40-man roster.
Phillips, 26, pitched to a 6.00 ERA in six games and six innings with the Orioles in 2012. He made 42 relief appearances for Norfolk, going 2-2 with a 3.17 ERA.
The Orioles can attempt to re-sign him, but he's free to sign with any team.
If the season started today, the Orioles would figure to use Troy Patton and Brian Matusz as their left-handed relievers. However, Matusz will be given a chance to win a job in the rotation in spring training.