Gattis will share time with Gerald Laird as the Braves await the return of catcher Brian McCann, who is recovering from shoulder surgery. McCann is expected to return by the end of April. Gattis hit six homers this spring.
Venters, who felt tightness in his elbow in his last spring training game, will be examined by Dr. James Andrews on Monday. Andrews performed ligament-replacement surgery on Venters' elbow in 2005.
Venters' injury cleared the way for the Braves to keep right-handers Cristhian Martinez and Anthony Varvaro on the 25-man roster. Both are out of minor league options.