NEW YORK -- Entering the eighth inning of another screaming-loud night at Citi Field on Saturday, Major League rosters across the continent featured only two position players meeting these criteria: at least 100 career plate appearances and zero home runs. One was Breyvic Valera, a Yankees utility man officially listed at 160 pounds. The other was Mets infielder Luis Guillorme, who had gone deep a dozen times in the Minors, but never in the bigs.

This wasn’t the spot where that seemed likely to change, even amid the backdrop of 43,875 fans -- thousands of whom bought their tickets in the days and hours leading up to the game. Nor did it have to. With the Mets trailing by a run, manager Mickey Callaway figured he would ask Guillorme to lead off the inning because of his ability to put bat on ball. Perhaps Guillorme could slap it to the opposite field, find some grass, turn over the batting order, make something happen. Throughout the Mets’ improbable charge up the National League standings, crazier things have happened.

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Such crazy things have happened, in fact, that after Guillorme blasted a pinch-hit, game-tying homer over the fence in right, clearing the route for the Mets to beat the Nationals, 4-3, and clinch a series win against their NL East rivals, several teammates said they saw the whole thing coming.

“It’s normal right now,” Jeff McNeil said.

Believe it or not, this is indeed the new normal for a Mets team that has won 15 of its last 16 games to move within a half-game of an NL Wild Card spot. This is the new normal for a Mets team so loose, so hot, so confident in its abilities that the players believe any one of them can be the daily star.

Saturday was Guillorme’s turn. Half an inning after Seth Lugo allowed a go-ahead homer to Juan Soto, snapping Lugo’s franchise record-tying run of consecutive outs at 26, Guillorme connected on his first career homer.

“It took a split-second to know,” Guillorme said. “I don’t hit many of those, so it was a great feeling. That was one of the balls I’ve actually known off the bat that it was gone.”

For the Mets, the rest was formulaic -- especially after Trea Turner committed a fielding error to put the potential winning run on base. McNeil followed with a single, the sold-out crowd thrummed and, a few minutes later, J.D. Davis hit a no-doubt sacrifice fly to give the Mets their first lead of the night. Lugo, who had entered a tie game in the eighth, retired the Nationals in order in the ninth to secure the victory.

“The way they were hitting there in the bottom of the eighth, that gave me another little boost of energy,” Lugo said. “And the crowd was already doing plenty of that.”

Judging by numbers, this was the Mets’ second-largest crowd of the season, trailing only their home opener, on April 4. Judging by decibels, it may have been their loudest. Fans began filtering in hours before first pitch, many of them donning the bright orange Hawaiian shirts the team gave away as a promotional item. The entire lot was buzzing from the Mets’ Friday night walk-off victory over the Nationals, which vindicated what the Mets had accomplished for weeks against lesser teams.

Their energy faltered only briefly, when starter Noah Syndergaard gave up two runs on a Soto homer in the first. The Mets drew even on consecutive homers from Davis and Wilson Ramos in the fourth, and Syndergaard did not allow another run through seven innings.

With that, the stage was set for Guillorme -- not only an unlikely candidate to homer, but an uncertain candidate to be on the roster at all. When the Mets signed veteran second baseman Joe Panik on Friday, team officials debated the merits of optioning Guillorme, who was batting .161, to Triple-A Syracuse instead of designating Adeiny Hechavarria for assignment. Ultimately, the team kept Guillorme, citing his left-handed bat as the reason.

“I’ve been up and down all year,” Guillorme said. “I was just happy they believed in me to help the team win.”

Why wouldn’t they? Guillorme is a Met, after all. At this point that seems to be more than enough of a prerequisite for late-inning dramatics.

"It's been pretty amazing how this team, this run, there have been a lot of guys who, the least expected come through,” Davis said. “Just like Luis, right now, tonight.”