Javy Guerra was what the Washington Nationals had left, once Saturday night turned into Sunday morning, once the rosters emptied onto the field, once Eric Thames stepped into the box and a long, loopy, look-away-and-you’ll-miss-something kind of game still hung in the balance.

The Milwaukee Brewers needed one run to nudge ahead in the 14th inning. That was it. But Thames plated two, with a towering homer to right, leaving Guerra shaking his head as he stared into the mound. That was the decisive hit in the Nationals’ 15-14 loss to the Brewers, one that stretched more than 5 ½ hours, far longer than the Nationals would have liked once they carried a three-run lead into the ninth inning.

Because long before the Nationals were done in by Thames, before the stadium finally emptied out, before the surrounding streets were filled with frustration and sleepy fans, a nagging problem came roaring back.

“I’m still searching for answers, to be honest, I don’t know,” closer Sean Doolittle said, voice hushed, eyes focused on the clubhouse carpet, after he blew his sixth save by giving up four runs on three homers in the ninth. “We keep trying to go back to the drawing board, we’re watching film, we’re looking at the metrics. I’m doing extra dry work before games, we’ve changed up a lot of my routine in the weight room, my maintenance and stuff. I just . . . ”

Doolittle paused as the rant ran out of gas. Then he shook his head.

“I don’t know,” he said. “It just wasn’t coming out tonight.”

Doolittle paced around the mound in the ninth, the brim of his hat tipped up, his face blank while another opposing hitter trotted around the bases. He had given up three home runs in the span of four batters — the first a solo homer from Christian Yelich; the second a game-tying, two-run shot from Mike Moustakas; and the last a backbreaking blast for Ryan Braun that put the Milwaukee Brewers ahead.

And so it was Doolittle, the Nationals’ closer, once the only reliable arm in the their bullpen, who stood at the center of a game that later slipped away. Again. Wander Suero had worked a scoreless sixth. Hunter Strickland did the same in the seventh. Fernando Rodney went one-two-three in the eighth, and that’s when Doolittle began to warm. This is the spot Manager Dave Martinez says he always wants to be in: the game on the line, the stakes never higher, the chance to put his best reliever in to shut the door.

But Doolittle has not been that shutdown closer from last year, or even earlier this year, as he battles the biggest workload of his career. He has never been used this much, and been this healthy, at this point of the calendar. He has now allowed 10 home runs in 52 ⅓ innings. The left-hander’s velocity hovered in the low 90s Saturday night. He was surprised, having felt fine in the bullpen, having figured he had enough to navigate through three outs. He didn’t.

The homers seemed to fly out in a blink, leaving a once-electric crowd in quiet frustration. Martinez walked out to get the left-hander. The reliever bounced the ball off the rubber before handing it over. The four runs ballooned his ERA to 4.33 — a number that rises to 7.36 in 15 appearances since the all-star break.

Martinez maintained after the game that Doolittle is healthy. He continues to express confidence that the 32-year-old can turn it around. But the manager did say he wants to talk with Doolittle soon, to see what’s going on, to see if they can find a solution before this spirals into more games. Doolittle admitted that he may have to rethink how he assesses his availability before each contest, since he has the tendency to tell Martinez he’s good to go.

“I’m not saying anything definitive, but I definitely want to have a conversation with Doo, and figure something out,” Martinez said. “What best for him, what’s best for the club and just make sure that he’s ready.”

“Yeah, we’re going to have to figure something out,” Doolittle said. “I’m going to have to figure something out. Because this team, they deserve better right now.”

He had blown the game, in every way he could, and that’s usually fateful for a closer. It comes with the territory. But the Nationals had a push left to bail him out, at least for a few innings, until he had to face a familiar round of questions and whatever step is next. There was, after all, still baseball left to play. That’s the game’s greatest equalizer.

So pinch hitter Yan Gomes drew a walk to lead off the bottom of the ninth against hard-throwing Josh Hader. And then Kurt Suzuki put runners on second and third with a double. And then Victor Robles poked a single to right, scoring Gomes, and that put the winning run on third base. The Brewers walked Howie Kendrick, loading the bases, and Trea Turner skied one to that kept going, and going, until it hooked just wide of the left field foul pole. A booming cheer settled into a lingering hum of anticipation. Hader then struck out the next three hitters, leaving everyone stranded, to force extras.

The Brewers took the lead in the 13th when Yelich homered off Guerra. But the Nationals tied it again, on a Robles sacrifice fly, and play dragged on. The Metro closed. Most nearby kitchens did, too. Then Thames took Guerra deep, unknotting the score, and Doolittle’s mistakes loomed large as the Nationals’ final rally petered out with pitcher Joe Ross at the plate.

The loss knocked Washington to 5 1/2 games behind the Atlanta Braves in the National League East. The Nationals are still alone atop the NL wild-card standings. But Doolittle’s mistakes loomed large by night’s end, and they will moving forward. Their closer isn’t getting the job done. Even 14 runs, and all kinds of offensive effort, isn’t enough to hide that.

“With how well we’ve been playing lately, with what’s at stake, with everything that this team can still accomplish, you want to be out there, you want to help the team,” Doolittle said. “But I haven’t been pulling my weight here these last couple weeks.”