Sledge hit his sixth home run of spring training and the Padres beat the Arizona Diamondbacks 7-6 in a split-squad game Saturday.
Matt Antonelli's three-run shot capped a seven-run seventh inning for San Diego.
"I'm happy I was able to come through," said Antonelli, a first-round pick in last year's draft out of Wake Forest. "The pitcher fell behind 3-0, so I knew I'd get a good pitch to hit."
Rookie outfielder Will Venable, son of former big leaguer Max Venable, had a two-run single.
Arturo Lopez was the winning pitcher and Mike Ekstrom worked the ninth for the save.
The game was played before a crowd of 5,847 in Yuma, the Padres' spring training home from 1969-93 before they moved to Peoria.