SAN DIEGO -- The Padres had a chance to salvage an important homestand on Sunday afternoon. It came unraveled in seven pitches.

Veteran right-hander Craig Stammen entered a 1-1 game against the Nationals in the top of the eighth inning, and he quickly found himself in a battle with pinch-hitter Howie Kendrick. On the sixth pitch of the at-bat, Stammen hung a curveball, which Kendrick rocketed off the left-field scoreboard.

From there, it happened too quickly to process. Two pitches later, Trea Turner took Stammen deep. Two pitches after that, Adam Eaton did the same. Then Anthony Rendon.

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When the dust had settled, the Nationals had back-to-back-to-back-to-back home runs and a four-run lead. The Padres, meanwhile, were on the cusp of a 5-2 loss, a .500 record (33-33) and a 4-6 homestand in which they couldn’t procure a series victory.

The stunned silence engulfing Petco Park told the story best: Stammen, who allowed three homers in his 79 innings last season, had given up four in the span of seven pitches.

“This is what it feels like when you give up a home run: You want to dig a hole, crawl behind the mound and go in that hole and never return,” Stammen said. “Every time you give up a home run. To give up four in a row, just times that by four.

“It doesn't feel good. But it's your job to go out there and make pitches. That's what I was trying to do. I didn't do it today.”

Stammen became the first pitcher since Jason Grilli in 2017 to allow four home runs in an outing that lasted less than an inning. The Padres hadn’t allowed four straight dingers since '06, when Jon Adkins and Trevor Hoffman combined to do so.

“I liked the first one, for sure,” said Nats manager Dave Martinez. “It put us ahead. Then it was: Wow, wow and wow!”

“It's not fun to go through,” said Stammen. “I guess you can say it happens. We need to figure something out and get better.”

In his three-year Padres tenure, Stammen has been a rock in the middle of San Diego's bullpen. He entered play Sunday with a 2.99 ERA as a Padre and a 3.27 mark this season. Even with some of Stammen’s recent struggles, there was no question who manager Andy Green would turn to in a tie game in the eighth.

“Craig's been a stud for two-plus years now,” Green said. “He's the guy we want on the mound in that situation. He's earned that right. He pitches great in that situation. It didn't happen. He'll bounce back because he always does.”

From the sixth pitch of his outing, it was fairly apparent Stammen didn’t have it. But things spiraled so quickly, Green didn’t have time to go to his bullpen.

“I'm sure Andy wanted to get me out of there as fast as possible, but somebody's got to warm up, too,” Stammen said. “You've got to think about the guy getting loose. You don't want to put a guy in that hasn't been warmed up. I've got to figure out a way to limit the damage.”

Green was asked about the logistics of his bullpen use. Miguel Diaz didn’t begin getting loose until after the second home run. Four pitches later, the Padres trailed by four runs and the game was effectively over. So what else could Green have done?

“Trust Craig,” Green said. “He's earned that trust time and time again. He still has that trust. He deserves that trust. It's baseball. You don't get the opportunity to see seven pitches in advance. You see it in hindsight. Nobody starts running to the bullpen with their eighth inning guy on the mound after one home run.”

Until that point, San Diego’s plan for a bullpen day had worked flawlessly. Three relievers combined for seven innings without an earned run.

Luis Perdomo was excellent over 3 1/3 frames, allowing only an unearned run after Ian Kinsler dropped a popup on the first batter of the game. Robbie Erlin and Trey Wingenter followed with scoreless ball, setting the stage for Stammen.

The Padres landed Stammen in 2016 on a Minor League deal. He was coming off multiple major injuries, which put his career in doubt and caused him to miss the bulk of the two previous seasons.

But Stammen won a big league job that spring, and he worked his way into a jack-of-all-trades bullpen role. Soon enough, his strong performance warranted setup innings. In the process, he became one of the most respected figures in the Padres’ clubhouse.

“He's our guy,” said closer Kirby Yates. “He's the guy takes the ball and everybody follows him. He never complains, he never whines, he never backs down from a challenge. He takes the ball every day whether he feels good or not.

“It didn't work out for him today. But he's the best option we have. You want him out there. It sucks. It's hard to watch when somebody goes through something like that, but he'll be fine.”