ST. PETERSBURG, Fla. -- Tampa Bay Rays ace Tyler Glasnow will undergo Tommy John surgery on Wednesday that will sideline him for the rest of this year and possibly all of next season as well.

The team announced the news during Tuesday night's 4-2 loss to the Seattle Mariners.

Glasnow has been on the injured list since June 15. The 27-year-old right-hander went 5-2 with a 2.66 ERA in 14 starts.

The news was not unexpected.

Glasnow visited Dr. Keith Meister on Saturday, at which time Rays manager Kevin Cash said surgery was the likely outcome.

The decision was finalized after a follow-up examination Tuesday.

Tampa Bay leads the American League East by one game over the Boston Red Sox despite having 15 pitchers on the IL.