Clayton Kershaw was crumbling again.

It was real. It was happening. It was October in July. It was deja boo.

It was the third inning of Kershaw’s long-awaited season debut against the San Francisco Giants on a sweltering Thursday afternoon at Dodger Stadium, and the future Hall of Famer was melting.

Having pitched two scoreless innings, he suddenly lost his touch and was in danger of blowing his moment.

In becoming the first pitcher in Dodger history to play 17 seasons with the team, Clayton Kershaw further ensured his greatness simply by his presence.

(Gina Ferazzi / Los Angeles Times)

He gave up a line-drive single to left by Jorge Soler, a ricocheting triple into the left-field corner by Tyler Fitzgerald, a hard single up the middle by Heliot Ramos, then another single to center by Matt Chapman.

Four smashed pitches. Two runs scored. Two runners on base. No outs. Oh no.

The last time Kershaw stood on this mound, he gave up six runs in the first inning against the Arizona Diamondbacks in an October playoff-opening loss that led to offseason shoulder surgery.

Nine months later, at age 36, he was improbably attempting a comeback that suddenly appeared stunted just three innings after it began.

The crowd grew silent. The warm wind ceased. The pitcher breathed deeply.

Then, as quickly as he lost it, Kershaw found it.

His strength. His speed. His season?

Then — in a three-batter sequence that screamed, “Remember me?” — Kershaw struck out Patrick Bailey swinging at a slider, struck out David Villar staring at a curveball and struck out Thairo Estrada swinging at another slider.

Three straight Ks, wow upon wow upon wow, Kershaw clenched his fist, the crowd emptied its lungs, the inning ended, and now the questions begin.

What exactly do the Dodgers have here?

Could their former ace actually fortify their battered rotation? Can he really pitch well enough during the next two months to play a role in October? He’ll surely never be a Game 1 starter again, but could he work his way into being a fourth piece who could contribute in a long series?

No matter where he fits, the Dodgers are delighted with the idea that they might have to actually make room.

“If this is the floor, then we’re in for a fun ride with Clayton this year,” thrilled manager Dave Roberts said.

In the Dodgers’ eventual 6-4 win, Kershaw waxed that floor to a shine, giving up two runs on six hits in four innings while looking both surprisingly marvelous and occasionally meh.

His fastball velocity averaged 90.6 mph, nothing special, but not terrible, and not slowly dipping. His slider and curveball were mostly working. He struck out six and walked two amid 72 pitches that mostly pleased him.

“It was fun,” he said afterward. “Definitely some things you can get better at, but overall it was a good day, and I can build off it.”

More than a day for stats, it was a day of the heart, Kershaw overwhelmed with a deep sense of appreciation for what he almost lost.

“It means a lot … to be able to get back out there at Dodger Stadium is something I thought about for a long time,” he said. “There’s a lot of people in here who spent a lot of time with me to help me get back … this was really cool.”

A crowd that braved 90-degree afternoon heat welcomed him with a standing ovation. He bowed his head while standing on the mound to the strains of, “We Are Young.” Dressed in cleats decorated by his children, he began pitching as if he never left, but this was different, this was special.

There were roars with every strike, louder roars with every out, and throughout the game enough noise to create a sense of reconnection.

“To go back out and pitch here … not that I ever did before, but I’m not going to take that for granted again,” Kershaw said.

The fact that he even took the mound was stunning. After watching him last October, didn’t you think he was done? This columnist sure did.

He’s won every imaginable award, he has a World Series ring, he’s headed to Cooperstown, why put himself through an arduous rehab simply to keep doing something he’s already done better than most human beings in history?

A crowd that braved 90-degree afternoon heat welcomed Clayton Kershaw with a standing ovation at Thursday’s game.

(Gina Ferazzi / Los Angeles Times)

Turns out, it was for moments like that third inning. He craves the competition. He relishes the hurdles.

“At the end of the day, you just got to perform, it doesn’t matter all the rehab, all the surgery, it doesn’t matter, you’ve got to perform,” he said. “Looking forward to my next start, thinking about that.”

In becoming the first pitcher in Dodgers history to play 17 seasons with the team — 17! — Kershaw indeed further ensured his greatness simply with his presence.

“Having a great season, a great first half, to be an All-Star, having a great couple seasons is one thing,” Roberts said. “But the longevity piece is something that I really admire, the consistency part, the ability to post, and so for him to set another record just speaks to the character, the competitor in Clayton Kershaw. And in all these years, he’s still been dominant, even without his best stuff. So to put him on the Mount Rushmore of Dodger players.”

Thankfully, Roberts is adamant that the Dodgers’ plans for the July 30 trade deadline will not be affected by Kershaw’s performance. They still need a frontline starting pitcher, and they seemingly already know better than to count on Kershaw so soon in his comeback.

“I don’t think this will have any impact on next week,” Roberts said. “I think that given where the starters are at, who we have and guys that are kind of not available, IL, I don’t think Clayton’s outing today has any impact on that.”

However, they definitely saved a spot for Kershaw if he’s ready.

“I expect Clayton to be a big part of October. Yes,” Roberts said.

How big? Stay tuned. The strange but necessary audition of a future Hall of Famer has begun.