Starting left-hander Jon Lester is flying to New York on Wednesday to undergo a procedure to remove his thyroid gland on Friday, manager Dave Martinez said prior to the Nationals' game against the Marlins.

The Nationals signed Lester, 37, to a one-year contract in January as their fourth starter. Martinez said the Nationals had been aware of the condition and were awaiting test results. After consulting with a doctor on Tuesday, Lester made the decision to have the gland removed during Spring Training.