It was a big night for the Padres.

And those inside Petco Park who stood and cheered loudly and chanted “Yuuuu” when Yu Darvish’s name was announced for the first time before Monday night’s game knew it.

It ended up being probably about what could have been expected for any pitcher’s first start in nine months.

Darvish’s season debut on Monday lasted 3⅔ innings, during which he allowed two runs, three hits, walked three, struck out five and threw 63 pitches.

“It feels good to be back,” he said later. “You know, a little bit nervous going back in there, but it’s definitely good to be back.”

He again was feted with an ovation and a sustained and throaty “Yuuuu” as he walked from the mound to the dugout at the end of his outing.

The magnitude of the night never hinged on the result for Darvish or the Padres, who ended up losing 6-3 to the Diamondbacks.

That the veteran right-hander is back and could potentially provide quality innings late is the hope upon which Monday’s start was made significant.

“Encouraging, very encouraging,” Padres manager Mike Shildt said. “… He’s only going to get better the more he’s out there. It was very, very encouraging outing for Yu. And it’s good to see him back out there and see number 11 on the mound for the Padres.”

The Padres began spring training believing Darvish would join Michael King and Dylan Cease atop a rotation that could help win plentiful games in the regular season and successfully navigate postseason series.

Darvish was shut down in spring training with what was called inflammation, and King has not pitched since mid-May due to a nerve issue near his right (throwing) shoulder.

King revealed Monday he will do some light throwing off a mound in the bullpen for the first time on Thursday. A rough timetable for his return from a nerve issue near his shoulder is sometime in August.

The Padres, who have gotten better than expected from Nick Pivetta (9-2, 3.25), Randy Vásquez (3-4, 3.79) and the various young starters who have filled out the rotation, will try to hold on until then. They will also hope Cease (3-8, 4.62) finds the consistency he has lacked.

Darvish reported feeling good after his outing. His next start is expected to come Saturday or Sunday before next week’s All-Star break.

“It’s a good thing to be back on the mound, back on the big-league mound,” he said. “You find out what you need to adjust, what you need to work on. So I’ll just keep making those just adjustments, keep working and looking forward to the next one.”

Darvish faced a good test in one of the major leagues’ best offenses.

The Diamondbacks arrived in San Diego reeling a bit, having lost eight of 11, but still ranking fourth in the major leagues in OPS and third in runs.

It did not seem in the first inning that Darvish had any rust.

While throwing seven different types of pitches, Darvish got nine strikes among his 10 throws. Half of the Diamondbacks’ swings were misses, including the two that ended strikeouts.

Staked to a 1-0 lead, Darvish found the second inning to be a challenge.

He deftly navigated what could have been a much worse frame after allowing the Diamondbacks to tie the game.

Darvish’s walk to Josh Naylor that began the second included two pitches that appeared to nick the bottom of the strike zone but were called balls.

Darvish was up 0-2 against the next batter, Eugenio Suarez, before Suarez grounded a double inside the bag at third base and all the way to the left field corner to bring Naylor home.

A full-count walk to Jake McCarthy, which also included a pitch that appeared to be in the zone, followed before Darvish got three straight outs.

He took 27 pitches to get through the second and just 12 more in the third, during which the Diamondbacks scored on a lead-off double by Corbin Carroll, a sacrifice bunt and Lourdes Gurriel Jr.’s single.

Yuki Matsui, who took over with a runner on first base and two outs in the fourth, allowed a two-run homer by Naylor in the fifth inning.

The Padres scored with help from an error in the first inning to take a 1-0 lead and scored with help from another error in the seventh to get to 4-2 before Arizona increased its lead to 6-2 with two runs in the eighth against Wandy Peralta and Eduarniel Nuñez.

Manny Machado, who in the fourth inning got his 2,000th career hit, belted his 357th career homer in the eighth inning.

Monday was the culmination of an extremely measured rehabilitation process in which the team deferred to the 38-year-old Darvish at every turn.

There was an expectation he would return in May after a rehab start for Triple-A El Paso went well. But Darvish reported “tightness” in his elbow afterward and did not throw off a mound with any intensity again until the first week of June.

A series of bullpen sessions followed, and after each one there was a wait to see how he would feel.

Darvish faced hitters in four simulated games over the past three weeks, the final one this past Wednesday in Lake Elsinore when he threw 64 pitches over four innings against players from the Padres’ low-A affiliate.

Given his age and the fact he has missed time with elbow issues each of his five seasons with the Padres, the team had maintained since before spring training they would be careful with Darvish this season. Whether it was via cutting back his between-starts regimen and/or finding pockets to eliminate starts, the priority was always going to be having him healthy for the end of the season.

They pointed to what he did at the end of last season after missing more than three months with an elbow ailment and then a personal matter. Darvish posted a 2.78 ERA over his final four regular season starts and then allowed the Dodgers three runs in 13⅔ innings in his two starts in the National League Division Series.

Darvish has been tinkering with different workout regimen and could alter his throwing routine to preserve his arm and body.

“We need to find a new routine,” Darvish said last month.

While he topped his 2024 averages with his four-seam fastball and sinker on Monday, he and others have also said recently that he might not throw as hard going forward.

“‘I think it was good to see 95-96 (mph),” Darvish said. “It tells you that you know your body is able to do that. So, definitely good to see those numbers. … Obviously, the goal is to try to stay strong and, you know, finish the season.”

Darvish throws more types of pitches more often than any pitcher in the majors, and he varies his usage of each pitch from start to start. On Monday, he threw a lot of spin. His most-used pitches were his curveball (14), sweeper (12) and slider (12). It was the latter he was most pleased to have used effectively and without negative effect.

“I was a little bit worried,” he said of throwing the slider. “It’s a little bit stress on the elbow area, and just to be able to throw that pitch without any issues, I think that was the positive part of about today.”