There would be a certain symmetry in the Eagles’ trading or releasing Zach Ertz this week, eight years after they drafted him, five months after what was, because of their terrible record and his injuries and decline in production, his worst season here. Ertz is an all-time Eagle: the player who scored the only Super Bowl-winning touchdown in team history, who holds the franchise record for most receptions by a tight end in a career and most receptions by anyone in a season. He and his family embraced Philadelphia and were embraced in return. No matter when he retires or where he retires to, he’ll come back to Philadelphia, and he’ll be welcomed whenever he does.

It’s understandable to get sentimental about Ertz and his time here, but the reason that his likely departure will have the feel of a loop closing has nothing to do with sentiment or the cold calculus that the Eagles, by waiting until after Tuesday to say a formal goodbye to Ertz, would create some salary-cap space for themselves this season. It has to do with when and why the Eagles drafted him and what he did for them once they did. Ertz was at once a standout individual player and part of a shift in thinking within the NFL about the tight end position. The Eagles caught a wave with Ertz and rode it to shore.

When the Eagles selected Ertz in the second round of the 2013 draft, they did so even though they already had what they believed to be two starting-caliber tight ends: Brent Celek, a team leader who had been with them since 2007, and James Casey, whom the Eagles had signed to a three-year free-agent contract earlier that offseason. They didn’t draft Ertz despite having Celek and Casey; they drafted Ertz because they had Celek and Casey.

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Just three years earlier, the New England Patriots had drafted two tight ends within their first six picks: Rob Gronkowski and Aaron Hernandez. Instead of playing one while sitting the other, Bill Belichick used both players in the offense at the same time, creating matchup nightmares for opposing defenses by forcing them to cover two big, fast tight ends with too-small defensive backs or too-slow linebackers.

Gronkowski and Hernandez combined for 87 receptions and 16 touchdowns as rookies in 2010 and for 169 catches and 24 touchdowns in 2011. In 2012, the Indianapolis Colts drafted Coby Fleener and Dwayne Allen. In 2013, the Cincinnati Bengals drafted Tyler Eifert, the Eagles drafted Ertz, and the Kansas City Chiefs drafted Travis Kelce. Belichick had kicked off a revolution.

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“Everybody started looking at it,” said Mark Dominik, who was the Tampa Bay Buccaneers’ general manager at the time. “You started looking at that two-tight-end set and realizing what kind of pressure you could put on defensive coordinators to try to commit. What are you going to do? You going to go out there in nickel? I’m going to beat you because I’m going to run the ball down your throat. If you go to base, I’m going to throw on you all day long. That’s a lot of pressure on defensive coordinators to figure out, ‘How do we not tip our hand here?’

“That’s where it really started, and it led to the Kelces of the world, the Ertzes of the world. And those guys keep moving up boards.”

They moved up so far that the player regarded as the best non-quarterback in this year’s draft — and perhaps the best player in this draft, period — was a tight end raised to a higher power: Archbishop Wood alumnus and University of Florida star Kyle Pitts, whom the Atlanta Falcons selected with the No. 4 pick. Pitts is a more refined, more dynamic iteration of those who were the mold for him: Gronkowski, Kelce, and, yes, Ertz.

Over Ertz’s career with the Eagles, his “low point,” such as it was, was the public criticism levied at him in 2016, when he didn’t throw a block during a loss to the Bengals in Cincinnati — hardly a surprising development for a fan base that expects its tight ends to play Demolition Derby at all times, that prizes the more traditional requirements and expectations for the position.

» READ MORE: The secret to the success of Archbishop Wood’s Kyle Pitts, the best player in the NFL draft | Mike Sielski

“But then, you shouldn’t care,” said Dominik, who analyzes the league for Sirius XM NFL Radio. “That’s not what they’re there for. They’re there to flex them out and see what the defense decides to do with you.”

Take the two most important plays of Ertz’s career: his fourth-and-1 catch for a first down late in the fourth quarter of Super Bowl LII, and his subsequent 11-yard touchdown to give the Eagles the lead in their 41-33 victory over New England. On each play, Ertz was on the field with the Eagles’ other (primarily) receiving tight end, Trey Burton, which assured that the Patriots could not double-team Ertz. In fact, in one of the most memorable sound bites from that game, you can hear NBC’s Cris Collinsworth say before the winning score: “Zach Ertz out wide, one-on-one.”

And it was on that play that Ertz showed his excellence and value to the Eagles. Safety Devin McCourty lines up opposite him. McCourty is 5-foot-10 and 195 pounds. Ertz is 6-5 and 250 pounds. Yet Ertz doesn’t overpower McCourty to free himself off the line of scrimmage. He simply runs past him, then cuts to the middle of the field to catch an in-stride pass from Nick Foles.

Ertz vaults into the end zone. McCourty, lying prone on the U.S. Bank Stadium turf, lifts his hands to his head in despair. The revolution eats its own. The Eagles beat the Patriots. There are worse lasting moments for a standout athlete in Philadelphia.