BALTIMORE -- A tough season for Stephen Pryor got worse this weekend as general manager Jack Zduriencik said the right-handed reliever is being shut down for the year after tests revealed a problem with his triceps muscle.
Pryor, 24, has been sidelined since tearing the latissimus dorsi muscle behind his right shoulder. He recently pitched four Minor League rehab games with Triple-A Tacoma, but began experiencing more problems in the right arm and had an MRI test Saturday that showed the new injury.
"Unfortunately, Stephen is going to be shut down for the remainder of the year," Zduriencik said. "It's a tricep injury, not necessarily related to the lat muscle. But he had an MRI yesterday and they didn't like what they saw. He'll be reevaluated and we'll look through this thing further, because it's really unusual."
Pryor pitched seven games for Seattle at the start of the season and didn't allow a run, while surrendering just three hits in 7 1/3 innings. He appeared in 26 games last year as a rookie, going 3-1 with a 3.91 ERA in 23 innings with 27 strikeouts.
Greg Johns is a reporter for MLB.com. Follow him on Twitter @GregJohnsMLB as well as his Mariners Musings blog. This story was not subject to the approval of Major League Baseball or its clubs.