PHILADELPHIA — This was supposed to be a night for the New York Giants to wrap up a playoff spot, add to the accomplishments of their recently overpowering defense and perhaps offer a hint that quarterback Eli Manning and their offense might be able and ready to contribute to a postseason run.

To the Giants’ dismay, it became a night that was about none of the above. Instead, they were left facing renewed questions about their viability as a legitimate Super Bowl threat in the NFC. And their 24-19 defeat Thursday to the Philadelphia Eagles at Lincoln Financial Field also served to greatly benefit the Dallas Cowboys, who clinched the NFC East title and the top seed in the NFC playoffs.

“We spotted them 14 points,” Giants Coach Ben McAdoo said. “They scored touchdowns. We kicked field goals. We turned it over three times. We didn’t handle the ball well enough. They won the penalty battle. We didn’t tackle well enough. … I didn’t coach well enough and we didn’t play well enough in all three phases.”

The Giants came up short on a night when Manning threw the ball 63 times and amassed 356 passing yards, when wide receiver Odell Beckham Jr. had 11 catches for 150 yards. The Giants amassed 470 yards of total offense but still failed to reach 20 points for a fourth game in a row. Manning threw three interceptions, one of which was returned for a touchdown.

“Let’s say it hasn’t been there, it hasn’t been there, it hasn’t been there and next week it’s there — I think everything goes out the window,” Beckham said. “Then you’re talking about the offense next week and what an explosive game they had, and not what we’re not doing. So it’s just timing. I truly believe it’ll all come together at the right time. But the time’s pretty much now.”

The Giants almost certainly remain playoff-bound. Their postseason spot could be clinched as soon as this weekend with a loss by any one of four teams: the Detroit Lions, Green Bay Packers, Tampa Bay Buccaneers or Atlanta Falcons.

But this was going to be a night for them to celebrate, not ponder the could-have-beens.

“Obviously we wanted to get the win tonight,” Manning said. “But we didn’t play well enough. We got off to a bad start, bad interception early on, and spotted them a 14-0 lead. After that we did some good things, moved the ball, made some plays, got down into scoring position a bunch and just too many field goals.”

The road to the Super Bowl in the NFC now officially goes through Dallas. And there is room to wonder if the Giants or anyone else can go there during the postseason and keep the Cowboys from moving on to Houston.

In recent weeks, the Giants had looked like the team that could do it. They’d beaten two NFC division leaders, the Cowboys and Lions, in their previous two games. That was their second victory of the season over the Cowboys. The Giants defense, remade with an offseason spending spree in which they handed out contracts totaling more than $200 million to free agents, had limited the Cowboys and Lions to a total of 13 points.

Manning had not really done his part. But he’d demonstrated during his career, with the Giants’ two Super Bowl triumphs, that he has potential postseason magic in him.

Yet with the prospect of clinching a playoff berth Thursday with a win, the Giants came out and promptly dug a hole for themselves early in the game. They faced first-half deficits of 14-0 and 21-6.

The defense was without cornerback Janoris Jenkins, who was on the inactive list after suffering a back injury Sunday against the Lions, as well as pass rusher Jason Pierre-Paul, who missed a third straight game since undergoing surgery for a core muscle injury. The Eagles, aided by the return of right tackle Lane Johnson from his suspension, moved rapidly to an opening-drive touchdown culminating with a 25-yard dash by running back Darren Sproles.

Manning forced a throw that was intercepted and returned for a touchdown by Philadelphia’s Malcolm Jenkins. A highly questionable unnecessary roughness call on the Giants when Eagles rookie quarterback Carson Wentz slid at the end of a run — even Wentz gets calls that Cam Newton can’t — preceded a 40-yard touchdown strike from Wentz to wide receiver Nelson Agholor.

The Giants pulled to within 21-13 before halftime on Manning’s touchdown pass to rookie wideout Sterling Shepard. A field goal made it 21-16 and, after Wentz exited the game to be evaluated for a possible concussion following a hit by defensive end Olivier Vernon that drew a penalty, the Giants stopped the Eagles on a fourth-and-goal gamble from inside the 1-yard line later in the third quarter.

But Manning threw another interception to Jenkins early in the fourth quarter. Wentz returned to lead a field goal drive, which the Giants answered with a field goal of their own. They drove to the Philadelphia 32-yard line late in the game. But a replay reversal negated a would-be first down on a catch by Beckham. A false start penalty made it fourth and sixth instead of fourth and one, and Manning threw incomplete toward Shepard.

The Giants got one more chance and reached the Philadelphia 34. But Manning overthrew an open Beckham on their second-to-last offensive play, then threw his final interception with five seconds left.

“We expect to score more,” Manning said. “We want to score more. I thought today we had opportunities to score more. We just didn’t.”

The Giants still are the one team that has demonstrated it has the winning formula against the Cowboys. But Pierre-Paul is not expected to return until late in the postseason, if then. It remains to be seen if Jenkins, who was selected this week to the Pro Bowl, will play at the same level when he comes back. Manning and the offense still are yet to show that they can do their share of the heavy lifting.

“It’s not the end of the season,” Beckham said. “We’ve still got another game to play. We’ve just got to wait and see what happens this weekend and then go out next weekend and take care of business.”