Kiermaier was diagnosed with a torn ligament in his right thumb and will undergo surgery, Marc Topkin of the Tampa Bay Times reports.
The 27-year-old suffered the injury while sliding headfirst into second base during Sunday's game against the Phillies, and subsequent tests revealed ligament damage that will require him to go under the knife.
A spokesman for the Rays says Kiermaier's surgery will be scheduled in the coming days. "We are all exhausted of KK getting hurt and there's nothing he can do about".
Right-handed pitcher Chih-Wei Hu was recalled from Triple-A Durham to fill Kiermaier's roster spot.
Kiermaier, much like the Rays (3-12), was struggling through the start of the season batting.163 with one RBI. Busting around to second base.
This will be the third straight season the two-time Gold Glove victor will miss significant time because of injury. The guy bobbles the ball. Last season, he fractured his right hip sliding feet first into first base and was out 61 games. "You'd like to see a little more reward for that than missing significant time, but this is three years running now where there is a chance he's going to miss a chunk".