NEW YORK -- As it turns out, the Mets are still capable of losing.

One of the best stretches in franchise history came to an end -- or at least a pause -- in the Mets’ 7-4 loss to the Nationals on Sunday. As they had so often throughout their run of 15 wins in 16 games, the Mets roared back from an early deficit in front of a raucous crowd at Citi Field. Only this time, they could not secure a victory, snapping their season-long winning streak at eight.

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They intend to let it roll right off them, given how completely transformed their outlook is from three weeks ago.

“Granted, we had an opportunity to sweep and it’s unfortunate that we didn’t, but we played some really quality baseball this weekend,” first baseman Pete Alonso said. “I don’t think there’s any doubt about that. We’ve been playing really well the entire second half.”

It was Alonso’s throwing error that sunk the Mets in Sunday’s finale, on a play that would have gone differently had pitcher Jacob deGrom gloved the ball at first base. As it was, three runs scored. Although the Mets fought back with four of their own, Asdrúbal Cabrera’s two-run double off Justin Wilson in the seventh proved to be the difference.

So here are the Mets, still very much alive and kicking. Their run of 15 wins in 16 games was the third longest one-loss stretch in franchise history, revealing several facts about them:

The rotation really is elite
Since the All-Star break, Mets starters have posted a 2.66 ERA, which ranks second in the Majors. More than that, they have averaged nearly 6 1/3 innings per start, the most of any team in baseball. That has not only kept the Mets afloat in just about every game they’ve played, but has also made the bullpen more effective.

Sunday, deGrom might have enjoyed a different fate had he managed to glove an Alonso throw at first base that was mostly on target. While Alonso blamed himself after the game (deGrom had to catch a flight with his family, and did not address the media), manager Mickey Callaway said that deGrom bemoaned: “I should have had that.”

If anyone is worthy of a mulligan, it’s deGrom, who has pitched his way back into National League Cy Young Award contention with a 0.92 second-half ERA. He, Noah Syndergaard and Zack Wheeler have all been at their best lately, which has allowed the Mets to construct lengthy winning streaks.

The lineup is deeper than Alonso, Jeff McNeil and Michael Conforto
No one doubts the abilities of that trio, but it’s three other Mets hitters who have opened eyes since the All-Star break.

One is J.D. Davis, who hit a one-out single in the second-inning Sunday to key the Mets’ three-run rally. Davis hit early this season, too, but started games only infrequently. Since becoming an everyday player when Dominic Smith landed on the injured list last month, Davis has produced a .383/.446/.809 line with five home runs in 15 games. He has been, without question, the most productive acquisition of general manager Brodie Van Wagenen’s tenure.

But he hasn’t been that much hotter than Amed Rosario, whose .344 average since June 29 ranks third in the NL over that stretch. Rosario’s hitting has vaulted him back up the batting order to the two-hole; for as long as Robinson Cano is sidelined, that’s where he’s likely to stay.

Finally, catcher Wilson Ramos has transformed from bust to boom over his last 15 games, hitting .316/.344/.561 with four home runs and 16 RBIs to make good on the first half of his two-year, $19 million contract. Plenty of questions remain regarding Ramos’ abilities behind the plate, as well as the desires of pitchers like deGrom and Syndergaard to throw to him. But for as long as Ramos is hitting, none of that seems to matter quite as much.

The Mets still can’t trust Diaz (but are going to keep trying)
Sunday, Edwin Díaz pitched with the Mets trailing by a run in the ninth. He walked a batter and allowed a Victor Robles two-run homer to increase his ERA to 9.39 over his last 25 outings.

“I try to have a positive attitude every single time,” Diaz said through an interpreter. “I’m just trying to get out of this rough stretch that I’m in right now.”

Now that the Mets have essentially moved on from Diaz as their full-time closer, they’re freer to use him, Seth Lugo and others in the spots that work best. But just because Diaz won’t be recording saves as frequently, doesn’t mean he won’t continue appearing in some of the Mets’ highest-leverage spots.

“At this point, the way we’re set up, we really can’t afford to do that,” Callaway said. “He’s going to continue to get big outs for us, continue to pitch in big games.”