SAN FRANCISCO -- Chad Gaudin was supposed to be a fill-in for Ryan Vogelsong, who is nearing a return from hand surgery. When Vogelsong does rejoin the Giants rotation, it's now very likely that Gaudin will be right there alongside him.

Gaudin threw seven scoreless innings Friday to pace a 2-0 win over the first-place Arizona Diamondbacks at AT&T Park, lowering his ERA to 2.15. Over his last four starts, Gaudin has give up just two earned runs in 231/3 innings.

"We'll cross that bridge when we come to it," manager Bruce Bochy said when asked about his rotation. "But he certainly has been so consistent. It'd be hard to take him out with the way he's throwing the ball."

Gaudin's way is a simple one right now.

"It's just how direct he is," closer Sergio Romo said. "Here it is, this is what I have. There are no gimmicks. It's impressive to watch his confidence. Everything he's been doing is a great lift for us."

The Giants needed a lift on Friday, when they had a chance to make an early statement and get back on the road toward the top of the division. Bochy and pitching coach Dave Righetti opted to put Gaudin on the mound for the start of the second half, and he cruised through his seven innings.

Gaudin allowed just three singles and struck out eight while tying a season-high with 92 pitches. The journeyman thought he had found a comfortable landing spot when he signed with the Giants last offseason, and when Gaudin made the team he said he was happy to do anything the Giants asked of him. His role has shifted from long man to late-innings reliever to starter, and all along Gaudin has dominated. He said the eight previous big league stops have helped him evolve as a pitcher.

"When I came up I had a lot different mentality," Gaudin said. "It was just kind of throwing, I didn't pitch. I learned the hard way that it's not always how hard you throw or how nasty you are. It's about going into the game with a game plan. That helps a lot. That takes a lot of the guessing out."

While Gaudin was dealing, the Giants jumped out to an early lead. Buster Posey had an RBI double in the first inning, and Hunter Pence followed two batters later with a run-scoring single. Ian Kennedy didn't allow another run after the early rally, but Gaudin didn't need the help.

He turned the ball over to a well-rested bullpen, and Bochy used four relievers while getting through a stressful eighth inning. With the bases loaded and two outs, Santiago Casilla got All-Star Paul Goldschmidt to hit a grounder to short. The outing was Casilla's second since coming off the disabled list last Saturday.

"It was a nice luxury to have," Bochy said of the four-pitcher inning. "You can't do that often."

The ninth inning was more traditional. Romo retired the side in order to extend his scoreless streak against the Diamondbacks to 29 games. The win was the fourth in five games for the Giants, who are 7-3 against the Diamondbacks this season and now trail them by 51/2 games in the National League West.

"We understand there are a lot of games to play, and we've got to play for today," Romo said. "Today was a great way to start the second half."

  • Vogelsong threw two bullpen sessions at the Giants' facility in Scottsdale, Ariz., over the break, setting the stage for the next step in his recovery. He will face a few teammates in a simulated game on Saturday at AT&T Park and could start an official rehab assignment early next week.

    "It all depends on how I come out of everything," Vogelsong said. "I'm assuming everything is going to go well."

    Barring any setbacks, Vogelsong could pitch for the Single-A San Jose Giants next week and then join Double-A Richmond after the Giants visit the White House on July 29. The tentative schedule calls for Vogelsong to start twice for Richmond and rejoin the Giants rotation around Aug. 9.

    "It's great news for us," Bochy said. "It's a soft schedule right now. He's going to have to get up to around 80 pitches. We're going to make sure he's ready."

    Vogelsong threw 62 pitches in a bullpen session on Wednesday and said he can throw all of his pitches without any issues.

    "It gets better every time," he said. "The timing is coming back, pitches are feeling better, and my mechanics are coming back."

  • Former Giants broadcaster Lon Simmons threw out the first pitch on his 90th birthday.

    Saturday's game

    Arizona (Wade Miley 6-7) at Giants (Matt Cain 5-6), 6:05 p.m., CSNBA