Max Scherzer crumbled in just about the worst possible manner Friday night, leaving Mets fans with little choice. 

They booed him. 

It was the expected reaction, given that the 38-year-old warhorse had imploded for a second straight start, with this one inflicting more damage on the Mets than the last. 

Scherzer, who allowed four home runs, wasn’t the only no-show for the Mets, just the most prominent in a 7-1 loss to the Padres in Game 1 of the wild-card series before a Citi Field sellout of 41,621. 

“Baseball can take you to the highest of highs and the lowest of lows and this is one of the lowest of lows,” Scherzer said after allowing seven runs, the most ever by a Mets pitcher in a postseason game. 

The Mets’ season now hinges on Jacob deGrom’s right arm. Manager Buck Showalter had hoped he could avoid using his ace this weekend — and had planned to start Chris Bassitt in Game 2 if the Mets won Friday — but will now deploy deGrom in an attempt to get this best-of-three series to Sunday. 

DeGrom’s start will be the first of his career at Citi Field in the postseason. The right-hander started four games for the Mets in the 2015 postseason, all of them on the road. 

“I have been in an elimination game before and was able to battle through that one,” deGrom said, referring to Game 5 of the NLDS against the Dodgers. 

The Mets will hope for a better version of deGrom than the one that allowed three solo homers in Atlanta in his last start before he departed with a blood blister forming on his right middle finger. DeGrom indicated after the game Friday that the blister isn’t an issue. 

“The finger is good,” he said. 

Scherzer exited to a chorus of boos with two outs in the fifth after allowing his fourth homer of the night — a screaming line drive to left off Manny Machado’s bat that buried the Mets in a 7-0 hole. 

It followed Scherzer’s performance in Atlanta last Saturday — part of a three-game sweep by the Braves that helped them win the NL East — in which he allowed four earned runs, including two homers, over 5 ²/₃ innings. 

Scherzer, who missed two September starts with an oblique irritation, was asked if there was anything that affected him physically Friday. 

“I don’t think so,” he said. “I felt good.” 

The Mets’ lineup was hardly blameless. Yu Darvish, who had manhandled the Mets in his previous two starts against them this season, posting a 0.64 ERA, allowed only one earned run over seven innings on this night. The Padres will send left-hander Blake Snell to the mound Saturday with the intent of delivering a knockout punch. The winner of this series will play Game 1 of the NLDS on Tuesday against the Dodgers in Los Angeles. 

“We have been really good and now we get to see what we’re made of,” Pete Alonso said. “I’m excited for [Saturday].” 

He added: “Two Cy Youngs going up against each other in a playoff elimination game. It’s going to be great.” 

Josh Bell hammered a two-run homer with two outs in the first inning against Scherzer after the game’s leadoff hitter, Jurickson Profar, reached on a broken-bat single. In the second, Scherzer recorded two fast outs before Trent Grisham’s homer to right field extended the Padres’ lead to 3-0. 

Scherzer appeared to find his groove by retiring seven straight batters before getting caught in a fifth-inning avalanche. Ha-Seong Kim singled leading off the inning and Austin Nola’s bloop double to right put Scherzer on the ropes. And then, it got worse: Profar lofted a fly ball to right that nestled just inside the foul pole for a three-run homer that started turning attention toward Saturday. Machado’s homer mercifully ended Scherzer’s night. 

“The expectations for Max are always high because of his track record, but we just didn’t score any runs,” Showalter said. “We knew Darvish was going to be a challenge and he was.” 

The Mets had early chances against Darvish, but failed to convert. In the first inning, Francisco Lindor was hit by a pitch and stole second. He reached third on Jeff McNeil’s single with one out, but Alonso struck out and Daniel Vogelbach flied out. 

Starling Marte, in his first action for the Mets in 4 ½ weeks, singled leading off the next inning and stole second and third, but Eduardo Escobar struck out before Tomas Nido was retired to conclude the inning. 

Darvish finally was dented in the fifth, when he allowed a solo homer to Escobar. Brandon Nimmo stroked a two-out triple, but was left stranded on Lindor’s pop out. 

“We are giving our best,” Lindor said. “It’s just today they landed the first punch.”