Kowar will meet with a doctor Friday to have his sore right arm examined, Ryan Divish of The Seattle Times reports.
The Mariners gave Kowar a couple days to rest and that evidently didn't knock the soreness out, so he's set to be evaluated further. It's not clear whether the soreness is in his elbow or shoulder. Kowar might have been pitching his way into a bullpen spot with three strikeouts over two scoreless innings this spring, but now it's possible he could be sidelined for a while.