SAN DIEGO -- Consider the brutal hit the Padres' bullpen has taken within the past five days: On Monday, they learned All-MLB closer Kirby Yates would need surgery on his right elbow to address bone chips. Four days later, Drew Pomeranz, Yates' replacement at the back end, landed on the injured list with a left shoulder strain.

Then consider what the Padres have asked of their remaining 'pen pieces: As their two most electric relievers were being shut down, the Padres had their relief corps cover a bullpen day Tuesday, extra innings both Wednesday and Thursday, and an impromptu bullpen day Friday. All that for a bullpen with a 5.86 ERA, ranked 27th in the Majors.

And yet -- somehow, some way -- the Padres won five straight games this week.

No, they didn’t add to their MLB record four-game grand-slam streak on Friday night. But the Padres' beleaguered relief corps stepped up instead in a 4-3 victory over the Astros at Petco Park.

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“Today we drew it up in the dirt,” said Padres manager Jayce Tingler. “In a way, that kind of fits our DNA and who we are.”

Tingler needed that many arms because Garrett Richards was forced into an early exit after two laborious innings. Richards threw 64 mostly high-stress pitches to get there. He stranded the bases loaded twice, and it took something bordering on a miracle for him to escape having allowed just one run.

The Padres mulled sending Richards out for a third inning. But the veteran right-hander is coming off 2018 Tommy John surgery, and the Padres weren't willing to push it. They like having a healthy Richards in their rotation, thank you very much.

“He wanted to go,” Tingler said. “That's the competitive warrior spirit in him. We went back and forth. You start going 64 pitches in two innings, you're entering the danger zone.”

Right-hander Javy Guerra followed Richards and was easily the most impactful bullpen arm of the night. Guerra has struggled immensely this season, and he's still waiting for the breakout the Padres envision. If it comes, it'll probably look like Friday night: Over 2 1/3 innings, Guerra held the Astros hitless, while striking out three and picking up his first big league win.

Of course, it'd be a bit unfair to grade Guerra on the same curve as the rest of the Padres' struggling bullpen. He was a career shortstop who was only converted into a pitcher last March. Guerra has thrown only 39 2/3 innings at any level. But because of his years as a shortstop, Guerra is out of options and can't be sent to the Minors, and the Padres certainly aren't prepared to give away an electric arm like his.

“What he's trying to do on the fly, it could possibly be the hardest thing for a pitcher that I've ever [seen],” said right-hander Emilio Pagán. “He's got what? Thirty career innings as a pitcher? And he's coming in, in big-time situations, trying to get Major League hitters out.

“Javy Guerra's stuff is arguably the best I've seen for any teammate that I've played with. He reminds me of an Edwin Díaz.”

After Guerra's lockdown effort, the Padres ran their lead to 4-1 in the fifth on back-to-back RBI knocks from Manny Machado and Jake Cronenworth.

From there, the overburdened bullpen held on for dear life.

“Gutsy,” Tingler said. “From all those guys.”

The Padres would’ve preferred to give Pagán the night off, after he'd blown a save Thursday. But they didn't have much choice. Tingler had already used Guerra, Matt Strahm, Craig Stammen, Cal Quantrill and Pierce Johnson in the build-up to the ninth inning.

Pagán also has struggled this season. But with Yates and Pomeranz on the shelf, the Padres need Pagán more than ever. He appears to be their de facto closer, and he responded with his first save of the season on Friday night.

“The only way I'm going to come out of this is by throwing more and getting on the mound more and seeing some results,” Pagán said. “I'm thankful … everybody's still believing me and giving me the ball in big-time situations.”

Maybe Pagán is right. San Diego's slumping bullpen needs its less heralded arms to step up. But first, those arms need to be given the chance to do so.

It helps that the Padres have rebounded from a five-game losing streak with a five-game winning streak. They improved to 16-12 on Friday night and currently sit in the National League West's second automatic playoff spot, two games ahead of the Rockies. That cushion gives the bullpen some breathing room with which to bounce back.

“I have full confidence that when it's all said and done, they're going to be one of the top bullpens in the game,” Padres catcher Austin Hedges said Friday afternoon. “We've got to play, normally, 162. We've got to play 60 now. But there's still plenty of games left for us to get those guys right, and they're going to be our horses when we get to the playoffs."

That's quite the statement from the catcher on a playoff-starved franchise: “when,” not “if.” But Hedges clearly has an awful lot of belief in his bullpen arms. And after Friday’s performance, why not?