SAN DIEGO -- Dave Roberts gave the San Diego Padres just the spark they were looking for.
Coming off a dreadful three-game sweep at the hands of the rival Los Angeles Dodgers, the Padres welcomed Roberts back from the disabled list and benefited from his hustle in a 7-2 win over the San Francisco Giants on Monday night.
Roberts beat out an infield single to keep alive a five-run seventh inning and scored on Mark Loretta's go-ahead, bases-loaded double with two outs.
Still, Phil Nevin pointed to Roberts' bunt single an inning earlier, when he slid headfirst into first base.
"Obviously, everyone's going to point to the balls that were hit that drove in runs tonight, but I go back to that bunt single by Dave that kind of added some adrenaline to us," Nevin said.
"Just to see him cross first base diving and pumping his fist, we just haven't had much excitement around here lately."
Roberts was erased by Loretta's grounder in the sixth, but the Padres managed to tie the game at 1-all.
Roberts missed the first 12 games with a strained groin.
"It was just a lot of pent-up adrenaline," Roberts said. "You're out there for the first two weeks of the season being a cheerleader, and to finally get out there and have an opportunity to contribute and get my uniform dirty, it's a good feeling.
"To come away with a victory and turn things around, I'm really excited. We've just got to keep building on it."
Roberts' hustle and Loretta's big hit were precisely what the Padres lacked for several games. They were embarrassed in a weekend sweep by the Dodgers, who outscored the Padres 18-3 and threw two complete-game shutouts.
Loretta's hit down the left-field line in the seventh came off Brett Tomko (0-3).
"I made a good pitch -- fastball in -- and got beat on it," Tomko said. "That's where I wanted the pitch."
With the game tied at 1-1, Ramon Hernandez started the rally with a one-out single to right and pinch-hitter Mark Sweeney drew a two-out walk. Roberts kept the inning alive with a chopper up the middle that shortstop Omar Vizquel couldn't handle for an infield single.
"He came up with a big at-bat," Nevin said. "He puts pressure on a defense. He made Omar come in and force him into a bad hop, and that kept that inning going."
After Loretta's hit, Brian Giles was intentionally walked before Nevin hit a two-run double to right-center to make it 6-1 and chase Tomko.
Tomko took a four-hitter into the seventh. The only run he'd given up was an RBI groundout by Nevin in the sixth. Tomko allowed six runs on eight hits in 6 2/3 innings, walked three and struck out none.
Giants rookie Lance Niekro hit his first career homer, a solo shot into the second deck in left in the sixth inning off Jake Peavy (2-0). Niekro, the son of Joe Niekro and nephew of Hall of Famer Phil Niekro, was called up on April 8 after Moises Alou went on the disabled list.
Niekro entered Monday's game after first baseman J.T. Snow left with a strained groin in the fifth. Niekro, who had five major league at-bats coming into this year, added an RBI double in the eighth.
Peavy struck out nine and allowed one run on six hits in seven innings. He walked one.
"He made very few mistakes. It was hard to get a feeling for what he was trying to do," Vizquel said. "Every time up, he worked you in a different way. He's pretty smart."
San Diego's Sean Burroughs hit a sacrifice fly in the eighth.
Roberts took the roster spot of SS Khalil Greene, who broke his right ring finger on Saturday night against Los Angeles. ... The Padres' seven runs topped their combined total from their previous four games, when they scored just six.