Yankees' Luis Severino to see doctor, get MRI for shoulder tightnessMeanwhile, Clint Frazier began his rehab assignment with Double-A Somerset8/14/2021, 9:18 PMAlex SmithEditorial ProducerNew York Yankees starting pitcher Luis Severino (40) throws as pitchers and catchers report for spring training at George M. Steinbrenner Field. / Kim Klement-USA TODAY Sports