SAN DIEGO -- Should the Padres have lifted Yu Darvish earlier? Heck, should they have let him pitch longer?

Really, those questions belie the point. Darvish was outstanding on Thursday night against Washington, cruising through eight innings and pitching into the ninth. On top of that, the Padres were facing a Nationals pitching staff with the sport’s highest team ERA. The ninth-inning maneuverings of manager Bob Melvin probably shouldn’t have carried so much weight in the first place.

This was precisely the type of game that a team in the thick of a mid-August playoff race cannot afford to lose. And yet, the Padres lost it -- a 3-1 gut-punch of a series opener at Petco Park against the team with the worst record in baseball. With the defeat, San Diego’s lead over Milwaukee for the final NL Wild Card spot dwindled to a single game.

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“It’s pretty tough,” said Juan Soto, who is facing his former team for the second series since he was dealt earlier this month. “You want to give a guy like [Darvish] the win. This is a great pitcher, and what he’s done today was unbelievable. It’s pretty tough, we couldn’t do anything for him.”

The Padres’ bats struggled again, with Manny Machado’s fourth-inning homer providing the entirety of the offense. Darvish, meanwhile, had thrown eight innings of one-run, three-hit ball, and he needed just 92 pitches to do so. Melvin opted to stick with the veteran right-hander for the start of the ninth inning – and that’s when things unraveled.

Two of the first three Nationals singled, before Melvin called on closer Josh Hader -- who hadn’t pitched in nine days. From the outset, Hader struggled. He plunked Luke Voit (his teammate for a few hours earlier this month), then walked Nelson Cruz, allowing the eventual winning run to score.

“I was going to let [Darvish] get two baserunners,” Melvin said. “I mean, I have to be right. I wasn’t. It didn’t turn out that way. But that was my thinking once the inning started.”

For most of the night, Darvish had been utterly dominant. He worked quickly and efficiently, and only Nats No. 9 hitter Ildemaro Vargas had made any loud contact -- a solo homer in the third and a clean single in the sixth. The only other hit Darvish allowed was a soft infield single.

Still, Darvish would be facing the top of the Nationals’ lineup, with a (very) well-rested Hader in the bullpen. In a rare show of postgame introspection, Melvin wondered aloud whether he should have lifted Darvish before the ninth.

“Maybe that’s the mistake -- was letting him start the inning,” Melvin said. “But really there were only two balls hit hard by the No. 9 hitter the entire game. The pitch count was under control, so that’s why I let him go back out there.”

It’s a moot point, of course, if Hader cleans up the mess -- as he’s done so often throughout his career. But the veteran left-hander has struggled over the past month. Nine days ago, he blew his first save with the Padres. Then, in his first outing since, he was thrust into a tough spot and came up empty.

“You’re going to have ups and downs,” Hader said. “We play 162 games for a reason, right? The way baseball goes -- I’ve been playing for a long time -- you’re going to have times where you’re going good and where everything’s tough. But you’ve got to keep that even-keel attitude.”

Indeed, it’s a long season that lends itself to peaks and valleys. The Padres have the distinct misfortune of acquiring Hader and first baseman Josh Bell amid the roughest stretches of their respective seasons. Bell went 0-for-4 on Thursday night and is now hitting just .125 in 15 games since he arrived alongside Soto from the Nationals.

“Those guys, they have the ability and they have the talent,” Soto said. “… They are great players and we have them for a reason.”

Melvin was quick to echo that sentiment, adding that half a month is far too small a sample to judge the Padres’ new acquisitions.

“You know, there are still a lot of games to be played, and I think things are going to get better,” Melvin said. “These guys are here for a reason. They’ve had great seasons to this point, and I’m confident it’s going to happen.”

For the sake of the Padres’ standing in the NL Wild Card race, the sooner the better.