The Japanese baseball phenom has reportedly suffered some damage to the ulnar collateral ligament in his right elbow. The injury was discovered during a physical back on November 28th that was performed by Dr. Masamitsu Tsuchiya at the Doai Kinen Hospital in Tokyo.

It is also reported that he underwent a platelet-rich plasma shot in late October in hopes of treating the elbow pain that was caused by the injury.

Ohtani signed with the Angels on Friday after several dominant seasons playing in Japan.

The injury is the least severe of UCL injuries, but any further damage could lead to Tommy John surgery. While it is serious, he will be able to continue full baseball participation with a program that will take care of his elbow.

Los Angeles paid a $20-million posting fee to Ohtani’s old club, the Hokkaido Nippon Ham Fighters, to sigh the 23-year old.