Stephen Pryor (groin) threw a simulated game on Friday and will begin a rehab assignment with Class-A High Desert on Sunday. After he pitches in a few games with the Mavericks, he'll head to Triple-A Tacoma before returning to the Mariners bullpen. He's been impressive in limited action, posting a 1.69 ERA through his first 5 1/3 innings with the Mariners, and will return to a setup role in the bullpen upon his return.