LOS ANGELES -- As the final sinker snapped out of the hand of Adonis Medina, of all people, and darted under Will Smith’s bat, the Mets completed one of the more improbable series splits they’ve had in recent memory. Medina earned his first career save in a game in which manager Buck Showalter used Edwin Díaz in the eighth inning, but not the ninth; in which the Mets won for the first time in 15 years at Dodger Stadium when trailing in the eighth inning or later; and in which the 5-4 victory in 10 innings gave them sole possession of the best record in the National League.

As much as they shied away from admitting it publicly, the Mets understood coming into Dodger Stadium that this four-game series would be a measuring stick. When they dropped the first two games in dispiriting fashion, the premature conclusions that followed seemed inevitable. Then the Mets won the final two in equally convincing ways, coming from behind on each occasion.

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“It shows how good we are,” said designated hitter J.D. Davis, who hit a game-winning RBI double off Craig Kimbrel in the top of the 10th. “We’re just as good as them.”

Davis was quick to offer respect to the Dodgers while also noting that the Mets are currently playing without Jacob deGrom, Max Scherzer, Tylor Megill and James McCann, which would place enough of a hurt on most rosters to knock them far down the standings. Instead, the Mets came away from Los Angeles sporting the second-best record in the Majors behind only the Yankees, thanks in part to depth pieces such as Nick Plummer, Trevor Williams and of course Medina.

Sunday’s original plan did not involve Medina, a 25-year-old reliever whom the Mets quietly acquired from the Pirates in April. But a cascade of events changed things after Showalter decided to use regular closer Díaz in the eighth inning against the Dodgers’ three best hitters: Mookie Betts, Freddie Freeman and Trea Turner.

When Díaz buzzed through that trio on 15 pitches, he told his manager he was willing to pitch the ninth, as well. But Showalter, concerned about having Díaz available on Monday and cognizant of the fact that the right-hander has rarely recorded multi-inning saves since joining the Mets, opted instead to use Seth Lugo. That decision backfired when Lugo allowed a leadoff homer to Smith and a game-tying, RBI single to Eddy Alvarez.

In the past, those types of blunders would routinely result in losses -- particularly here, at Dodger Stadium, where the Mets not so long ago suffered 12 consecutive defeats. Yet this version of the club seems different in a hundred ways. So it wasn’t altogether surprising when Lugo escaped the ninth, Davis drove home Pete Alonso in the 10th, and Medina stranded the potential tying and winning runs on base to end the game.

“To have the team have that trust in me to pitch in that big spot, it’s really been everything for me,” Medina said through an interpreter. “I love being part of this team.”

Added Eduardo Escobar, who hit a go-ahead sacrifice fly in the eighth: “He came out here and threw like a veteran, like a big boy that he is.”

Williams called the win “a testament to our grit,” which has become a common phrase around the Mets’ clubhouse. Whether it’s seven-run comebacks in Philadelphia or five-run ninth innings in St. Louis, the Mets seem to figure out a way to achieve this sort of thing on the regular. That they’re doing so without deGrom (who recently began throwing bullpen sessions), Scherzer (who should be back next month) and Megill (who could return as soon as this week) has only served to further embolden the Mets. They know they’re good. They also know they can be even better.

There is, of course, a long way to go, as Showalter cautioned in saying “there’s a heartbreak and an uplift around every corner.” But if April showed the Mets that they are a good team, and May made them the kings of the NL East, then this Dodgers series demonstrated that they’re capable of beating anyone, at any time, in any fashion. Davis defined it as more of a “quiz” than a test, noting that the road to the pennant will almost certainly go through this same Dodgers team.

Whatever it was, the Mets certainly passed it.