Auburn Doubledays
Fletcher was drafted by the Washington Nationals in the 14th round, with the 431st overall selection, of the 2018 MLB draft. In 2018, he played for the Gulf Coast Nationals and the Auburn Doubledays, going 2–1 with a 2.90 ERA in 31 innings. He pitched for the Hagerstown Suns, Potomac Nationals, and Harrisburg Senators in the Washington organization in 2019, going a combined 5–4 with a 1.79 ERA in 60 innings.