Los Angeles Angels two-way phenom Shohei Ohtani's sophomore season is over. On Thursday, the Angels announced Ohtani will undergo a procedure on Friday to "address a bipartite patella" in his left knee. The club estimated his recovery will span 8-12 weeks, or into the winter.

For those unfamiliar with the condition, it reportedly impacts just 1 to 2 percent of people and "means their patella is made up of two bones instead of one," according to Heathline. Additionally, it tends to be an incidental discovery. It's unclear how and when Ohtani was diagnosed, given he played on Wednesday night. 

Ohtani, of course, spent this season exclusively as a designated hitter following Tommy John surgery last fall. He fared well in his limited role, hitting .286/.343/.505 (122 OPS+) over 425 plate appearances. Ohtani ranked as the third most-productive Angel at the plate among qualified hitters, just behind Mike Trout and Tommy La Stella. 

Ohtani is the second Angel to be shut down in recent days, as the club announced reliever Cam Bedrosian would miss the rest of the year due to a strained forearm on Wednesday. Outfielder Justin Upton, meanwhile, underwent an MRI on his knee on Wednesday and his availability is uncertain moving forward. 

The Angels rank fifth in baseball this season in days lost to injury, with 1,403, per Spotrac. The New York Yankees, San Diego Padres, Philadelphia Phillies, and Pittsburgh Pirates are the only teams with more days lost.