SAN DIEGO -- For a short-lived moment on Wednesday afternoon, it was OK for the Padres to dream. Dinelson Lamet was back on the mound, and he was electric, striking out four Brewers across two innings at Petco Park. The San Diego rotation has been one of the best in baseball this year, and here was Lamet -- one of the best pitchers in baseball last year -- joining that mix.

The moment proved agonizingly fleeting.

The good vibes surrounding Lamet's return from the injured list lasted all of 29 pitches in the Padres’ 4-2 loss to Milwaukee on Wednesday. In the dugout after his second inning, Lamet began to experience tightness in his right forearm. He retreated to the trainer’s room, and reliever Craig Stammen quickly got loose. Sure enough, Lamet exited early because of right forearm tightness -- crushing news after he’d spent the offseason recovering from a UCL strain in his right elbow.

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Afterward, the Padres hoped for the best. Manager Jayce Tingler noted that Lamet never pitched through any pain, adding that perhaps Lamet caught the injury before any serious damage took place. The reality is: The Padres just won’t know until Lamet undergoes an MRI later this week. 

“We’ll have to wait and see, ultimately, what the doctors say,” Tingler said. “You think of all the work he’s done to get to this point.”

Lamet first sustained his elbow injury last September during his final start of the 2020 regular season. He would miss the postseason, but Lamet said doctors informed him that his early shutdown would help him avoid Tommy John surgery.

Instead, the Padres opted for a platelet-rich plasma injection and rest, before a late build-up for the season. He was brought along slowly during Spring Training, as the team exercised caution at every step. He made his Cactus League debut during the final week of camp and missed the first three weeks of the regular season.

“We’ve gone step by step, a slow process, and we’ve had build-up -- from bullpen, to live BP, to simulated games, into game action,” Tingler said. “The only thing I could think of is: Just a little more adrenaline today that maybe fired something up, because we just haven’t seen [any issues] over the last two months.”

Even in a rotation full of aces, Lamet’s dazzling stuff stands out. He posted a 2.09 ERA last season, the best qualifying mark for a starter in franchise history, and finished fourth in NL Cy Young Award voting. Without Lamet, the Padres' rotation is still a dominant one, boasting the likes of Yu Darvish, Blake Snell and Joe Musgrove. With Lamet, it would’ve been perhaps the best in baseball.

“He’ll bounce back,” Stammen said. “He’s one of those guys -- you can’t keep him down long. He’s going to bounce back, and he’ll be great for the Padres in the future.”

In a way, however, the Padres were preparing for this moment as far back as December. With Mike Clevinger on the shelf following Tommy John surgery and Lamet still a question mark, general manager A.J. Preller began the trade binge that brought Darvish, Snell and Musgrove to San Diego.

In an ideal world, the Padres would’ve added Lamet to that group, and they’d have a quartet of aces. But if Lamet’s elbow trouble resurfaced, they also wanted to be certain they had a deep enough group of arms to weather the storm. Now that depth could be set for a serious test.

Left-hander Adrian Morejon underwent Tommy John surgery on Tuesday and will miss the remainder of the season. The bad news kept coming on Wednesday.

With Lamet’s return, Chris Paddack and Ryan Weathers appeared to be vying for one place in the rotation. Now it seems likely they both stick. There’s also the possibility that, down the road, Lamet’s injury provides opportunity for MacKenzie Gore, the sport’s No. 1 pitching prospect according to MLB Pipeline. But Gore’s debut doesn’t appear imminent, given the number of off-days the Padres will have over the next three weeks.

As if Lamet’s injury weren’t enough, San Diego finished its homestand with a 1-5 record and a particularly excruciating loss on Wednesday. The Padres stranded 11 baserunners, bringing their Major League-leading total to 161. They loaded the bases with nobody out in the eighth and didn’t score. They put the tying runs in scoring position in the ninth, and Eric Hosmer whiffed on a high Josh Hader fastball to end it.

A four-game series at Dodger Stadium looms this weekend. The Padres enter with a taxed bullpen that was asked to cover seven innings Wednesday. Weathers, once the long-man in that bullpen, will take the ball in the opener.

Wednesday’s loss dropped the Padres to 10-10 -- not where they wanted to be in late April, but not a debilitating start either. They started the 2020 season 11-12 before finishing 37-23, the second-best record in the National League. That was in a 60-game season. This year, they’ve got more than five long months left to play.

“We’ve just got to keep grinding,” said third baseman Manny Machado. “You don’t win a championship in April.”

Still, it’s not so much the .500 record as it is the circumstances surrounding that record. Fernando Tatis Jr. was injured early, and hasn’t looked like himself -- at the plate or in the field. The offense has squandered huge opportunities on a near-nightly basis. The defense has committed a Major League-leading 18 errors.

The Padres have taken some punches in early April. For the most part, those issues are fixable. But a long-term injury to Lamet -- perhaps the most electric arm in a rotation full of aces? Well, that would qualify as a different kind of haymaker.