SAN DIEGO -- Sometimes it takes a go-ahead homer in the top of the ninth to highlight just how invaluable Brock Holt is to the Red Sox.

Holt, wearing "BH" on his jersey for Players' Weekend, teed off on a 93-mph fastball on the inner, lower half of the plate by All-Star closer Kirby Yates and sent it over the right-field wall to fuel Boston to a tense, 5-4 victory over the Padres on Saturday night at Petco Park.

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It was the first pitch Yates threw in the top of the ninth, and it put the Sox back on top after the Padres stormed back from an early 4-0 deficit.

To understand how unlikely the occurrence was, consider this: Yates entered the outing having allowed just one homer in 50 appearances this season. Holt had hit just two homers in 194 at-bats.

What led to Holt’s third, and biggest, homer of the season?

“Just trying to get a good pitch to hit and put barrel on it. Obviously you don’t want to get too deep into the count against him and have to deal with the splitter,” said Holt. “Fortunately I was able to get a good pitch on that first one and put a good swing on it.”

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And what led to Yates doing the thing he does so infrequently -- giving up a long ball?

“Made a bad pitch, guy hits it out of the park,” said Yates. “It happens. You don't like it, make better pitches. Trying to go down away, and it leaked back middle. I yanked it a little bit. They've got good players, man. They're all good hitters. Their young guys are studs, their veteran guys know how to work at-bats. It's just a tough lineup.”

And that’s where sometimes Holt can get lost in the shuffle -- at least when it comes to outside recognition. The Red Sox have Mookie Betts, J.D. Martinez, Rafael Devers, Xander Bogaerts and Andrew Benintendi -- all dangerous hitters who are on everyone’s radar.

Then there is the under-the-radar Holt, who is slashing .342/.409/.493 in 176 plate appearances since coming back from the injured list on May 27.

“He’s a good hitter,” said Red Sox manager Alex Cora. “I’ve been saying all along, we missed him the first month, month and a half. He’s an important part of what we’re trying to do, as far as matching up and playing second and all that. He’s healthy and swinging the bat well, and he’s a good at-bat.”

So maybe the Red Sox didn’t expect Holt to go deep against Yates, but they did expect he would do something productive. “Put him in any spot and it seems like he comes through,” said Saturday's Red Sox starter, Nathan Eovaldi.

Eovaldi takes step forward

Speaking of Eovaldi, he took a positive step in his buildup back to the starting rotation.

Living up to his Players’ Weekend nickname of “Nitro,” Eovaldi topped out at 100.1 mph and averaged 97.5. He breezed through the first two innings, facing the minimum of six batters.

But he seemed to run out of gas in the fourth, when he gave up a single to Manny Machado and a two-run homer to Eric Hosmer that slimmed Boston’s lead to 4-2. Cora took him out after that.

“Felt really good out there,” Eovaldi said. “Made a few mechanical adjustments, and they seemed to work for me. I don’t know if it was just being on the bases or what, but in the third or fourth inning I kind of tired out a little bit. Tried to go out there as long as I could.”

Bullpen-ing again works for Cora

With each game so big for the Red Sox right now -- they trail the Rays by six for the second American League Wild Card spot -- Cora continues to manage with urgency.

After Eovaldi’s shorter-than-expected effort, Cora leaned on six relievers for the final 19 outs, and they delivered. Josh Taylor allowed a baserunner he inherited from Ryan Brasier to score and tie the game in the seventh, but he bounced back by striking out Machado with the bases loaded. Brandon Workman navigated out of a jam in the ninth and struck out the side to earn his eighth save.

“They’re doing a good job,” said Cora of his relief corps. “We said it in Spring Training: stuff-wise, we’re pretty good. Just a matter of don’t overdo it. It’s not easy, but we talk about the off-days, this part of the schedule was going to benefit us, and the weather helps, too.”

If the Red Sox are going to pull off a sweep of the Padres on Sunday, they’ll need another big effort from the bullpen on a day swing man Brian Johnson is going to get the start.