SAN FRANCISCO -- A resident of Northern California, Reds reliever David Hernandez had plenty of family and friends at Oracle Park on Saturday. None were more important than his two sons, ages 9 and 7, and several hours before Cincinnati played the Giants, Hernandez was on the field playing catch with his boys and having a good time.

But when the time came for Hernandez to be summoned from the bullpen to pitch the seventh and eighth innings, he was all business. The right-hander struck out five of his six batters while the Reds bullpen combined for five scoreless innings with just one hit allowed in a 5-4 victory.

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“I thought I was going to be tired running around the outfield for three or four hours, chasing them around,” said Hernandez, who lives outside of Sacramento and turns 33 on Monday. “They definitely keep me young, keep me spry, keep me nimble. It’s always fun to be able to compete in front of them and see me do hopefully what is a good job.”

On a night when starter Anthony DeSclafani wasn’t at his best, both the Reds’ bullpen and their offense were there to pick him up. Cincinnati took a 3-0 first-inning lead on Joey Votto’s RBI triple and Yasiel Puig’s two-run homer, but San Francisco jumped ahead, 4-3, with a three-run bottom of the fourth.

DeSclafani was finished after four innings with four earned runs and eight hits allowed. Manager David Bell was ready to put the 4-4 game in the hands of his bullpen after the Reds evened it on Eugenio Suarez’s homer to begin the top of the fifth.

“I didn’t feel like he was quite as sharp tonight. He was missing a little bit in the middle of the plate with some of his pitches,” Bell said of DeSclafani. “Could he have gone back out and thrown two scoreless innings? Yeah, we believe in him that much. That was the decision I felt had to be made there. We had a fully rested bullpen.”

First, Robert Stephenson pitched a scoreless fifth inning and gave way to lefty Amir Garrett for the sixth. A blooped single by Steven Duggar as Nick Senzel and Jesse Winker collided, followed by a wild pitch, put the go-ahead run in scoring position. Donovan Solano walked to bring up Joe Panik and in a pivotal play, Duggar tried to steal third base and was called out on catcher Tucker Barnhart’s throw and Suarez’s tag. The call was challenged unsuccessfully by the Giants, and it proved big. After Panik walked, Garrett recovered to strike out Stephen Vogt.

In the seventh, the Reds took the lead when Suarez led off with a double and later scored the go-ahead run from third base on Dietrich’s two-out blooped single. Then it was up to Hernandez to hold the lead.

Given the middle of the Giants’ order, he struck out the side -- Evan Longoria, Pablo Sandoval and Mac Williamson -- with fastballs that were all 94 mph.

Then in the eighth, Hernandez sandwiched Kevin Pillar’s flyout between strikeouts of Brandon Crawford and Duggar.

“Bro, that’s probably the nastiest,” Garrett said. “Something’s got into David, because he’s striking out guys with bases loaded, striking out guys. Striking out what, five today? I don’t know who that guy is. He’s somebody else. I love that fight in him, that bulldog in him. That’s awesome. That’s what our team needs right there, for situations to arise like that.”

Since he gave up three runs on April 28, Hernandez has retired 21 of 24 batters in seven scoreless innings over six appearances.

“You wish you had that stuff every night. I had some extra motivation with a lot of family being here and being so close to home,” Hernandez said. “You never want it to snowball on you in front of your family and friends. You just have to make some pitches, execute. That’s a very good, scrappy, talented lineup.”

Raisel Iglesias, who had a blown save and two losses as he struggled last week, had his third straight strong appearance. In the ninth, he retired the side in order with two strikeouts and collected his eighth save.

“That was really overpowering tonight,” Bell said. “That was as good as we’ve seen him all year.”

The Reds have won three straight games -- including two over San Francisco to put them in position for a series sweep on Sunday. Cincinnati’s pitching staff, which has been maligned in recent seasons for its struggles, now leads the National League with a 3.18 ERA. The bullpen has an NL-best 3.28 ERA.

Hernandez credits the coaching staff for helping relievers know where hitters’ weaknesses are early in counts to increase the importance of getting ahead and limiting baserunners.

“I think our bullpen just stays ready. We’re prepared,” Hernandez said. “When our starters get into trouble, they’re not afraid to give us the bulk of the innings. I just think our preparation going into each series is something that I’ve never seen before, as far as just scouting and putting together a game plan. I think that’s something that’s just completely different than what we did last year. So far, it’s working.”