Upton has been on the disabled list since July 14 with a right abductor muscle strain. The Braves started him on a minor league rehab assignment Wednesday. He collected four hits, including three doubles, in 12 at-bats for Triple-A Gwinnett.
The Braves signed Upton to a five-year contract in the offseason, but have not received production to match the deal from the speedy outfielder. Upton, 28, has hit just .177 with a .565 OPS and seven stolen bases in 2013.
To make room for him on the roster, catcher Gerald Laird was placed on the DL. Laird had a kidney stone removed on Wednesday. He did not travel with the team to Philadelphia. When the Braves need to give catcher Brian McCann a rest, they will likely use rookie Evan Gattis at the position.