Nationals' Sean Doolittle: Advances to mound work

Doolittle (elbow) has begun throwing bullpen sessions, Bobby Blanco of MASNSports.com reports.

The hope is that Doolittle can advance to live batting practice sessions sometime next week and begin a minor-league rehab assignment soon after. He's on track to join the Nationals' bullpen around late April or early May, and is coming off surgery last July to repair a partial tear of the UCL in his left elbow.