Oviedo allowed two hits and struck out four over 3.1 scoreless innings in Saturday's spring start against the Rays.
After a wild, rocky start to the Grapefruit League, Oviedo has impressed in two subsequent outings and is the frontrunner for Boston's final rotation spot. That first spring appearance, when the right-hander walked three and hit a batter, has been followed by 6.1 scoreless innings with eight strikeouts and zero walks.