SAN FRANCISCO -- For the second consecutive start, left-hander Alex Wood found himself playing stopper for the Giants, firing seven innings of one-run ball to lead his club to a 5-2 win that denied the Cardinals a three-game sweep on Wednesday night at Oracle Park.

In his final start before the All-Star break, Wood allowed only three hits while walking two and striking out six, lowering his ERA to 3.67 over 15 starts this season.

“I thought that was a pretty gritty and tough outing from him, and it was exactly what we needed,” manager Gabe Kapler said.

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The Giants have struggled to cash in on scoring opportunities over the last week, but they strung together enough big hits to back Wood, who also halted San Francisco’s season-high four-game losing streak by defeating the D-backs on Friday.

Paul Goldschmidt’s RBI single cut the Giants’ lead to 3-2 in the eighth, but Darin Ruf provided extra breathing room by crushing a towering two-run shot to straightaway center field off Justin Miller in the bottom half of the inning. Ruf entered the game in the sixth to replace first baseman LaMonte Wade Jr., who departed with a left hand strain. Wade, who has been filling in for Brandon Belt, incurred the injury during his second at-bat of the night and will be re-evaluated on Thursday’s off-day.

With the win, the Giants created more separation at the top of the National League West, moving 1 1/2 games ahead of the Dodgers, who were walked off by the Marlins for the second straight night. San Francisco has now been in first place for 38 consecutive days dating to Memorial Day and will aim to maintain that coveted perch as it closes out the first half with a three-game series against the Nationals this weekend.

“I’m just so happy for a lot of guys in our clubhouse and our team in general,” Wood said. “We’ve played such good baseball over the first half of the season. To be going into the last three games this weekend and having a one- or two-game lead in a division with two of the best teams in baseball -- from that standpoint, it’s hard to ask for much more.”

Signed to a one-year, $3 million deal over the offseason, Wood opened the regular season on the injured list with a lower back strain, but he missed only two weeks before returning and establishing himself as a key member of the Giants’ rotation. The 30-year-old veteran hit a rough patch in June, when he logged a 6.94 ERA over five starts, but he turned it around after regaining his feel for his wipeout slider.

Over his last three starts, Wood has allowed four earned runs over 17 1/3 innings. He stymied the Cardinals primarily with his slider and his sinker, which drew four whiffs and 18 called strikes.

“I’ve known Alex Wood since he was 10 years old in Charlotte, and it’s been fun to watch him grow and compete,” Cardinals manager Mike Shildt said. “He’s a really good kid, he’s a good competitor, he’s got good stuff and I’ve seen him compete really well against us. That’s the best I’ve seen him throw in the big leagues, and that’s saying something. This guy was on a world championship club last year and has pitched in big games for the Dodgers in the past and now over here with the Giants. Had some good life to his fastball, he’s changing speeds, I thought he threw the ball exceptionally well.”

Minor fracas in the second
The Giants entered Wednesday batting only .175 with runners in scoring position over their previous nine games, but they finally got a timely hit in the second when Mike Yastrzemski doubled to knock in fellow Vanderbilt alum Curt Casali and put San Francisco ahead, 2-1.

A mild skirmish then ensued between Yastrzemski and Cardinals starter Johan Oviedo, who thought the Giants’ right fielder was stealing signs. An irked Oviedo stepped off the mound and yelled at Yastrzemski to “shut the [expletive] up,” though Yastrzemski said had “no clue” what pitches the Cardinals were calling for.

"That's part of the game, the mental side,” Yastrzemski said. “Any advantage that we can take, whether teams are paranoid, whether they think we're doing something that we're not, it's just a way to hopefully get a distraction off the hitter and to get it onto the baserunner so they can't make their pitches. I definitely think that he had a lot of intent thinking that I was relaying signs, which I wasn't. I had nothing.”