The Eagles and quarterback Carson Wentz can force a tie atop the NFC East standings with a win over the Cowboys next week. (Toni L. Sandys/The Washington Post)

PHILADELPHIA — An unsettling notion started to sprout here as fall ceded to early winter, an idea that could not taint or diminish last year — nothing could — but threatened to spoil the afterglow. What if it was a fluke? What if the Philadelphia Eagles’ Super Bowl triumph was only a blip, a one-year anomaly, a cherished achievement here, but a source of confusion everywhere else?

Monday night’s 28-13 victory over the depleted Washington Redskins preserved the Eagles’ title defense but did little to quell those uncomfortable thoughts nagging at the city. The Redskins lost their quarterback and both starting guards, and yet the Eagles could not put away a team quarterbacked by Mark Sanchez until midway through the fourth quarter. They won, and so their season stayed alive. They showed promising signs, but proof they are a caliber of team capable of repeating never materialized.

“We’re a long way from that,” Eagles right tackle Lane Johnson said. “I promise you.”

The Eagles won consecutive games for the first time all season, but their locker room late Monday night was more subdued than celebratory. It contains enough champions for them to understand victories over the New York Giants and quarterback-starved Redskins do not mean they have turned any kind of corner.

Those victories, which came on the heels of an embarrassing, 48-7 shellacking in New Orleans, only nudged them to 6-6, still in the thick of the NFC wild-card picture and one game behind the Dallas Cowboys, whom they will face Sunday in Dallas in a season-shaping showdown, in the NFC East race. The magnitude of the looming game mattered more to Philadelphia than the minor achievement of consecutive wins.

“We’ll see after this week,” safety Malcolm Jenkins said. “We understand where we are as far as the season. While we were excited about putting two wins together, if we don’t take care of business this week, it’s all for naught.”

The case for the Eagles remains faith-based. To believe they can become a dangerous playoff threat, you have to believe they can recapture the magic carpet ride of last season. The problem is, that may be impossible. Their defense has been ravaged by injuries, although reserves Rasul Douglas and Nathan Gerry made the biggest plays of the game for Philadelphia’s defense Monday night — a key open-field tackle and an interception, respectively.

Last year, when Frank Reich was the offensive coordinator, the Eagles ranked eighth in third-down conversion percentage and second in red-zone scoring. This year, with Carson Wentz coming off knee surgery and Reich the head coach in Indianapolis, they’re 11th and 19th. The difference has trickled over to their defense, which thrived last year when it played less than half the game and could rush the passer with abandon.

“We’re built to play with the lead,” tight end Zach Ertz said.

While the Eagles have plenty of problems to sort through, the fact that they’re not dead yet matters. Beating the Giants and Redskins may not be cause to throw a parade, but it signals that the Eagles are not going to start polishing their Super Bowl rings and start planning for the offseason.

“We could have easily tanked when we lost how we lost against the Saints,” defensive end Brandon Graham said. “Usually when you lose that bad, you tend to see some things you don’t like. Luckily, it wasn’t that. Everybody came in the next day ready to go, ready to get that sour taste out.”

The Eagles, charmed all of last season even after Wentz tore up his knee, have learned how to play through rough patches. In the third quarter Monday, holding only a 14-13 lead, Wentz threw an interception to Redskins cornerback Josh Norman in the end zone. But Philadelphia’s defense held, and the Eagles asserted control on their next possession.

“So much bad stuff has happened this year that you kind of get immune to it now,” Johnson said. “We have to move on.”

Monday night was far from a masterpiece, but the Eagles could find promise, especially in wide receiver Golden Tate’s performance. In Tate’s first three games after coming from Detroit in exchange for a third-round pick, Wentz completed 11 of the 20 passes he threw in Tate’s direction for only 97 yards. Monday night, Wentz completed all seven of his targets to Tate for 85 yards and the receiver’s first touchdown as an Eagle, plus a two-point conversion.

“Tonight just felt really organic,” Tate said. “We just went out there and played ball. I didn’t think anyone was trying to get me the ball too much. It worked the way it worked. It just so happens statistically, I had a decent game. This week, it just felt like we went out there and played, had a great week, just let it all happen the way it’s supposed to happen.”

The Eagles had not scored on an opening drive since Week 6, but their first possession Monday night was a beauty. The Eagles held the ball for 7:29 as they marched 75 yards on 12 plays. Wentz finished the drive by escaping the pocket, scrambling and rifling a throw on the run to Tate in the corner of the end zone, the ball zipping just past the outstretched hand of a cornerback.

The Eagles had made a fast start a priority, knowing the Redskins entered 0-5 when the other team scored first. Their fast start stalled, but in the end, they did enough to keep their hopes alive. Now comes Dallas, a stiffer test and a truer sign of just what will happen to these Eagles.

“Everything is still right in front of us,” Graham said. “Like we tell everybody every week: Don’t count us out.”

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