The Giants recalled Walton from Triple-A Sacramento prior to Thursday's game in Atlanta.
Walton will assume the 26-man active roster spot of outfielder Luis Gonzalez (back), who was placed on the 10-day injured list. Gonzalez had been filling a near-everyday role in the corner outfield for the Giants, but Walton is more likely to serve as a utility man while he's up with the big club than as a replacement for Gonzalez in the lineup. San Francisco could get another lefty-hitting corner outfielder in LaMonte Wade (knee) back from the IL as soon as this weekend, in which case Walton would be a candidate to head back to Triple-A.