The Eagles’ vaunted defense was lousy against the Lions, and Jonathan Gannon has lost any benefit of the doubt

DETROIT — As the Eagles, in single file, trudged through a tunnel from the Ford Field turf into the stadium’s visitors’ locker room, Brandon Graham smiled that thousand-lumen smile of his, and Miles Sanders kept saying, “Big dubs, big dubs,” repeating it loud enough for anyone nearby to hear, as if he were trying to remind everyone of the final score. Sure, a big W for the Eagles over the Lions, 38-35. Big to win on the road. Big to start 1-0. But the truer evaluation came from a media member particularly close to the team, who nuzzled up to Graham and told him: “They’re going to kill you tomorrow.”

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Maybe just a good scolding will suffice. Maybe just for now. The nicest thing that anyone can say about defensive coordinator Jonathan Gannon and the unit he supervises, based on what happened here Sunday, is that it was Week 1, and Week 1 in the NFL can be nutty and unpredictable, and perhaps those factors explain why the Lions gashed the Eagles for 181 rushing yards. Why they averaged 6 ½ yards per rush. Why they were 9-of-14 on third down. Why the Eagles sacked Jared Goff just once — on a play in which Goff happened to drop the snap. Why Goff threw for 215 yards but could have thrown for 100 more, had the Lions not dropped three of his passes and had he not missed several open receivers. Maybe. Perhaps.

Save one of those errant Goff throws — one that Kyzir White deflected and that James Bradberry intercepted and returned 27 yards for a touchdown — the Eagles did little to stymie a Detroit offense that is closer to The Slowest Show on Turf than it is the reincarnation of the 1999 St. Louis Rams. Gannon and his defense placed more pressure on their own team’s offense than they did on the Lions’, forcing Nick Sirianni, play-caller Shane Steichen, and Jalen Hurts to be at their best just to keep the Lions at arm’s length. The Eagles led by 14 points once and 17 points twice, and still their defense barely touched Goff, couldn’t tackle D’Andre Swift, and allowed Detroit’s wide receivers to run free too often.

“We should have kept that 17-point lead,” Graham said, “but at the end of the day, like Coach said, when you mess stuff up on the details, that’s when stuff starts slipping away.”

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It was easier to write off some of the criticism of Gannon last season as a product of the Eagles’ talent on defense and their opponents’ talent at quarterback. Patrick Mahomes, Tom Brady, Justin Herbert, Dak Prescott, David Carr: Most teams would struggle to stop that group. But Goff isn’t in that class, and if the questions about Gannon and his soft-coverage approach weren’t answerable last year — was he having the Eagles play that way out of necessity, because their personnel was so poor, or out of his own preference? — a whole new round of doubts manifested themselves Sunday.

Was this disappointing performance on the players or on Gannon? How long will it be before Jordan Davis begins to take snaps away from Fletcher Cox at defensive tackle? How long will it take a defense with five new starters to gain a better sense of communication and cohesion? And how long will it take for Haason Reddick to be the force he was supposed to be? He insisted that Gannon had, in the phrase coaches and players around the league love, put him in the right position to make plays. Yet Reddick made just two tackles Sunday, and Gannon frequently had him fall back into coverage instead of sending him on search-and-destroy missions after Goff.

“I slipped twice when I could have had two sacks,” Reddick said. “Weird [stuff], you know? But I’m flushing it. I’m going to go watch this game, learn from it, and then move on. It’s only Week 1. Everybody has to fix some mistakes: them, us, other teams around the league.”

That was the Eagles’ mantra in the aftermath of Sunday’s game: Watch the film. Clean it up. Move on to the Minnesota Vikings next Monday night. “But we were able to get a win,” Sirianni said. “In this league, on the road in your first game, we’ll take it any way we can get it.” This problematic showing on one side of the ball doesn’t just disappear, though. All those offseason and preseason acquisitions by Howie Roseman — Reddick, Bradberry, Davis, Nakobe Dean, C.J. Gardner-Johnson — eliminated most of the explanations and excuses that Gannon could once wield as a shield. Yes, it might take time for this defense to jell, but Roseman ultimately shifted the burden of proof from himself to Gannon. No one can argue that the carpenter doesn’t have decent tools now. It’s on him to build something solid.

Sunday was supposed to be the start of that process. Instead, it was a thrill ride that scared every Eagles fan to death, and a sense of calm arrived only after Hurts burrowed forward for a yard on fourth-and-1 with 66 seconds left, with the clock running, with no one in Philadelphia wanting to see Jonathan Gannon’s defense on the field again.

“Faith,” Sirianni said, when he was asked why he went for it on that fourth down. “Faith in the players.”

He meant the ones on offense. The ones on defense, and the man who coaches them, have a long way yet to earn such trust.

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