Boston Red Sox' Jackie Bradley Jr (R) celebrates as he...

Boston Red Sox' Jackie Bradley Jr (R) celebrates as he and Rafael Devers (C) score on a two run double in front of New York Mets catcher Kevin Plawecki (L) during the fifth inning at Fenway Park in Boston, Massachusetts, USA, 15 September 2018.  Credit: CJ GUNTHER/EPA-EFE/REX/Shutterst/CJ GUNTHER/EPA-EFE/REX/Shutterstock

BOSTON — Mickey Callaway has broached the subject from certain angles before, in describing Jeff McNeil as a prototypical No. 2 hitter and praising his defense and bat-to-ball skills, and this time the Mets’ manager said it in more concrete terms.

Callaway would be happy if McNeil is the Mets’ starting second baseman in 2019, but he stopped short of calling that his outright preference.

“I have to see how the offseason goes,” he said. “I know we’re going to be comfortable either way.”

And either way, McNeil used the Mets’ 5-3 loss to the Red Sox on Saturday to continue to piece together a strong body of work for the club — and its eventual new general manager — to consider this winter. He had one of the Mets’ two hits and laid out for another tip-of-the-cap-inducing catch in shallow rightfield.

The grab came in the sixth. J.D. Martinez fisted Drew Smith’s first-pitch fastball toward right. McNeil, shaded toward the second-base bag, sprinted onto the outfield grass and leaped for a full-extension grab.

“That was unbelievable,” Callaway said. “Laid out, full extension. Doesn’t get any better than that. That was one of the better plays I’ve seen all year.

“You don’t teach that. That’s him getting a good read off the bat and not giving up on the ball ever and just going for it.”

BOSTON, MA - SEPTEMBER 15: Jeff McNeil #68 of the...

BOSTON, MA - SEPTEMBER 15: Jeff McNeil #68 of the New York Mets comes down with the ball after making a diving catch in the sixth inning of a game against the Boston Red Sox at Fenway Park on September 15, 2018 in Boston, Massachusetts. (Photo by Adam Glanzman/Getty Images) Credit: Getty Images/Adam Glanzman

Said McNeil: “I saw he got a little bit jammed on it, so I knew it wasn’t going too deep in the outfield, and I got a really good break on it.”

It was the second night in a row McNeil made such a catch. On Friday, he lunged to his right and laid out to snag a line drive off the bat of Jackie Bradley Jr.

Callaway said McNeil’s defense has been “way beyond” what he expected when the Mets promoted him to the majors in late July.

“He continues to impress us, not only at the plate but in the field,” Callaway said. “We’re glad we’re getting this long look at him going into the offseason, that’s for sure.”

McNeil stood out in a nondescript game. With the loss, the Mets (69-79) helped the Red Sox (102-47) inch closer to clinching the American League East title. Combined with the Yankees’ 8-7 loss to the Blue Jays, Boston’s magic number is down to four.

The Red Sox took the lead for good with a two-out, four-run rally in the fifth inning as Bradley and Brock Holt each had a two-run double.

The Mets didn’t have a hit until the fourth, when McNeil lined a single to rightfield through the shift. Brandon Nimmo’s three-run homer off Rick Porcello into the Red Sox bullpen — just beyond the reach of rightfielder Mookie Betts, who was hanging over the wall — minutes later accounted for all of the Mets’ runs. Porcello had five strikeouts and one walk in five innings.

Corey Oswalt lasted 2 2⁄3 innings and allowed one unearned run, a product of Dominic Smith’s throwing error in the first inning. Paul Sewald allowed four runs in two-thirds of an inning, and four other relievers combined for 4 2⁄3 scoreless frames.

Daniel Zamora struck out four of his five batters.

“It was really good. [Zamora] spins the ball really well. He doesn’t give in,” Callaway said. “He sneaks his fastball in there when it’s convenient to get them off that slider, and he continues to execute. The thing I’ve noticed that’s pretty impressive about him is even if he gets to 3-and-2, he goes out there and throws that slider again and throws it for a strike and makes them make a decision.”