For nine months, Ron Rivera has preached culture change. He was hired to right the ship and lead the Washington Football Team on a new course, trying to fix a franchise that had struggled both on and off the field for much of the last 20 years. He used slogans and four-letter words, along with a personable approach and military mind-set to inspire a team mired in disaster. His message was simple.

“We’re not going to quit,” Rivera said Thursday ahead of Sunday’s season opener.

At an empty FedEx Field on Sunday, his players gave a performance that indicated they have bought into his process. Washington rallied back from a 17-point deficit, led by a stellar performance from its remade defense, to defeat the Philadelphia Eagles, 27-17, in Rivera’s Washington coaching debut.

Washington’s defensive line, stacked with five first-round draft picks, annihilated Philadelphia quarterback Carson Wentz with eight sacks for a loss of 62 yards, while its secondary came up with two game-changing interceptions that sparked a turnaround by the offense.

“One thing that I tried to focus on is that we’ve gone through a lot and things have been tough, but they stuck together, they didn’t point any fingers, they didn’t blame anybody, they just kept hammering away,” Rivera said. “I’m not sure who played that first quarter for us in burgundy, but I like what they did in the second, third and fourth quarters. The guys responded very well and stuck to the game plan.”

The bruising by the defense bought time for Washington’s young offense. For much of the first half, visions of years past returned as the offense sputtered — a three-and-out to start, with as many negative plays as completed passes in the first 28 minutes of play. Second-year quarterback Dwayne Haskins, in his first Week 1 start, connected on only three of his first 12 pass attempts, and five of the team’s first six drives resulted in punts. The sixth? A hooked 48-yard field goal attempt by Dustin Hopkins.

All the while, the Eagles, with a tight end corps that ranked atop the league last season in both catches and receiving yards per game, took advantage of mismatches in coverage. Wentz quickly connected with Dallas Goedert and Zach Ertz for a total of 33 yards and a touchdown on Philadelphia’s opening drive.

Washington’s defensive line struggled to rein in its energy in the early going. Rookie defensive end Chase Young was flagged for a critical neutral zone infraction, giving the Eagles a free five yards and first down en route to the end zone, and his new sidekick, Montez Sweat, added one of his own on Philadelphia’s subsequent drive.

To many, the Washington Football Team showed the same colors — the same mistakes, the same knack for beating itself, but with a new name and new uniforms.

But it wasn’t long before Washington’s line wrecked the game — and Wentz — and the team of old gave way to something new.

In the span of six plays in the first quarter, Wentz was sacked three times, the first of which was courtesy of veteran Ryan Kerrigan. Kerrigan, who was relegated to a reserve role behind Young in Jack Del Rio’s 4-3 defense, recorded two sacks to pass Dexter Manley and become the franchise’s all-time sack leader, with 92 in his career. He capped his day with a fumble recovery after a strip-sack by Daron Payne and Young.

“Pretty crazy,” Kerrigan said after. “I mean, this organization has been around for a long time and a lot of really good players have come through. To get to the top, that was pretty special for sure.”

Yet the turning point Sunday came from a different source — Fabian Moreau’s interception with less than two minutes remaining in the first half. Moreau stepped in front of rookie receiver Jalen Reagor to grab the ball at Philadelphia’s 45-yard line, giving Haskins and the offense another try to put up points before the break.

Haskins delivered, connecting with Terry McLaurin and Dontrelle Inman for 21- and 11-yard completions, respectively, before finding Logan Thomas — Haskins’s favorite red-zone target in training camp — in the middle of the end zone.

“Everyone was amped up on the sidelines,” Moreau said. “We knew coming out of that this was our game — our game to prove ourselves.”

During the halftime break, Rivera received an IV, as was planned by him and the team’s lead doctor and athletic trainer, to ensure he stayed hydrated on the sideline. He had begun cancer treatment only five days earlier.

“I basically told one of our operations guys, ‘Hey, look, I’m getting my IV so I might not be out in time, so somebody’s going to have to make sure somebody steps up to the podium,’” Rivera said. “Apparently Dwayne stepped up and it was a pretty ruckus one from what I understand.”

Haskins gave the halftime speech, reminding his teammates the Eagles were visitors.

“He got everyone riled up and put it on his back,” Moreau said. “Like a leader.”

Roughly three minutes into the second half, cornerback Jimmy Moreland picked off Wentz and set up Haskins at Philadelphia’s 20. Again, the offense took advantage, with a one-yard touchdown run by Peyton Barber bringing the deficit to 17-14.

Washington tied the game at 17 on Hopkins’s 38-yard field goal less than a minute into the fourth quarter, and took the lead on a three-yard scoring run by Barber, which capped a 13-play, 48-yard drive with a little more than six minutes remaining. Hopkins added an insurance field goal with 3:29 left.

In all, five of Washington’s final eight drives led to scores for 27 unanswered points, and Haskins, who mustered only 77 passing yards in the first half, completed 10 of 15 passes in the second half for 101 yards. Yet those five scoring drives began in Philadelphia territory, thanks to a defense that served as a catalyst and reason to believe maybe, just maybe, Rivera is on to something. Maybe Washington really is beginning to change.

“This is a good group of guys and I kind of think when we started scoring points and started stopping them on defense, all of a sudden, these guys realized we can play with these guys,” said Rivera, who was awarded the game ball by his players. “It was really kind of fun to see because these guys are capable. There are a lot of young guys on this team, and if we do it right and grow it right, who knows where we can go?”

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