Withrow, 26, sat out last season while recovering from back and elbow surgeries. He made 46 total relief appearances for the Dodgers in 2013 and 2014 and posted a 2.73 ERA over 66 innings with 71 strikeouts and 31 walks.
The Braves acquired Withrow as part of a six-player trade with the Dodgers in May. The Dodgers selected Withrow with the No. 20 overall pick in the 2007 draft out of Midland (Texas) Christian School.