Left-hander Aaron Thompson, a rising prospect in the Nationals' farm system, has been promoted from Class AA Harrisburg to Class AAA Syracuse.
Thompson, 23, was 1-1 with a 2.87 ERA in three starts for the Senators. In Syracuse, he'll take the rotation spot vacated by Luis Atilano, who made his big-league debut for the Nats last night.
Acquired from the Marlins last summer for first baseman Nick Johnson, Thompson impressed club officials this spring, posting a 1.42 ERA in three appearances. He's seen as a strong candidate to reach the majors before season's end.