PHOENIX (AP) " Gorkys Hernandez didn't know until he got to the ballpark that he'd be in the lineup.
Obviously he was ready, though.
With Denard Span out due to tightness in his hip, Hernandez took over in center field and the leadoff spot, driving in four runs to lead the San Francisco Giants past the Arizona Diamondbacks 8-4 on Tuesday night.
Hernandez singled home two runs in the second inning and doubled in two more in a five-run fifth.
"You have to be ready all the time," he said. "You never know what's going to happen, especially on the bench. You've got to be ready just in case when the boss says, 'You ready?' I'm ready."
The Giants bounced back after blowing Sunday's season opener by allowing two runs with two outs in the ninth inning.
"Gorkys, what a great day he had for us," manager Bruce Bochy said. "He wasn't scheduled to play. We had to insert him in the lineup and he had four RBIs, had good defense, got some big hits. I've said this so many times: The bench plays such an important role during the season."
Johnny Cueto went five innings for the win despite giving up home runs to Jake Lamb and Paul Goldschmidt.
Cueto allowed four runs on six hits, struck out five and walked two. He got on base twice, once when he slapped the ball past first base for a single in a sacrifice bunt situation, the other on an error.
After new closer Mark Melancon blew the save in Sunday's 6-5 defeat, four Giants relievers combined to allow one hit over four scoreless innings this time.