Smyly, a second-round pick in the 2010 draft, was nails in the minors last season. He had a 2.26 ERA and 131 strikeouts in 127.2 innings, compiling an 11-7 record.
To make room for Smyly, the Tigers designated Clete Thomas for assignment, a move that could spell the end of Thomas' stint in Detroit. The Tigers have 10 days to trade him or will place him on waivers, at which point he could be claimed by any team. If he clears waiver, Thomas will remain with the Tigers organization and be sent to triple-A Toledo.
Through five games, Thomas hadn't started or had an at-bat.
Rays starter Jeff Niemann will be pitted against Smyly. Niemann spent part of 2011 in the minors but has shown he can, at times, thrive in the majors. Last season the 6-9 Niemann had a string of 10 straight starts without a loss, and is 2-1 with 3.48 ERA in five appearance against the Tigers.
The first pitch Thursday is scheduled for 1:05 ET.