Eagles training camp: The first day had the usual good vibes. The hard part will be making them last.

You might have heard that Wednesday was the first day of Eagles training camp, which it was. You also might have heard a fair number of players and media members referring to Wednesday as “the first day of school,” which it sort of was. And you might believe that the first day of school is a drag, which is bogus. The first day of school gets a bum rap. The first day of school is great. On the first day of school, the weather is usually warm and sunny, and you see your friends and classmates for the first time in a couple of months, and there are introductions and reintroductions and a sense of optimism in the air: new year, new subjects to explore, new experiences to be had. The first day of school rules.

It’s the second day of school that’s the rough one. The second day of school means actual classwork and actual homework. The second day of school is when the grind really begins, because the novelty and freshness of the first day have worn off, and concentration must be summoned and attention must be paid, and the third day is just around the corner. And the fourth and fifth days after that. And your geometry teacher might turn out to be a taskmaster. And you might not understand the difference between gerunds and participles. And what do you mean I have to write a three-page essay entirely in French?

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Think of an NFL training camp and a three-game preseason and a 17-game regular season in the same manner, and you’ll see why there’s value in the mostly canned coachspeak that Nick Sirianni served up during his news conference before Wednesday’s practice. Better yet, you’ll understand why the task the Eagles have in front of them — returning to and winning the Super Bowl this season after they lost it last season — is so daunting.

“Let me make this first point perfectly clear,” Sirianni said. “The goal of it right now, right this second, is not to get back to the Super Bowl. That’s not our goal right now. And I know everyone’s going to say, ‘Well, that’s a crazy thing to say.’ Our goal is to get better today. You can’t win two games unless you win one. Our goal is to get better and prep for our first game against New England. And we’ll take those things day by day with how we go about our process.”

This is the only approach that Sirianni and the Eagles can take: They have an elephant on their dinner plate, and there’s only one way to eat the thing; one bite at a time. Sirianni doesn’t have to say they’re shooting for a Super Bowl. No one does.

“Everyone knows what the goal is around here,” A.J. Brown said. “I don’t even have to speak on it.”

If anything, the more they talk about looking into the relatively distant future, the less likely they’ll be to get back to the big game, because human nature is human nature, and most of them know how hard it was to get there just once. Some of them even won one 5½ years ago and can remember the challenge of revving back up again after a shorter offseason full of celebration.

“It was a lot more fun last time,” Jason Kelce said.

Shaking off that disappointment is not easy. Recent history shows as much. Of the last 20 teams to have lost a Super Bowl, just one — the 2018-19 Patriots — won it the following year, and just four teams equaled or improved their regular-season record from their championship season to the next. Sirianni said Wednesday that the Eagles, as is their philosophy, have done some deep research dives into the factors that prevented those teams and more from duplicating their success. He cited two — injuries, particularly to the quarterback and offensive line, and general offensive regression — off the top of his head.

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“You do want to look at why,” Sirianni said. “There are a lot of different analytical studies that you want to do: why teams win first games, why teams win Thursday night games, why teams don’t repeat success coming back from the Super Bowl. So you look at some of the common denominators of teams that have struggled coming out of winning or losing a Super Bowl. And you put those together, and you get answers. Maybe you don’t get it always completely: ‘This is exactly what it was.’ It’s never black and white. There’s some gray to it.”

No denying that. You might have a star wide receiver demand a new contract, declare war on the quarterback and pretty much the entire organization, and split the locker room in half, as Terrell Owens did in 2005. You might lose Tom Brady to a knee injury in Week 1, as the Patriots did in 2008. You might have your offensive coordinator make a puzzling call on fourth-and-goal in an elimination game, as the Falcons did at Lincoln Financial Field in January 2018. There’s no telling what problems and circumstances will present themselves over the next few months. All the Eagles can do is keep showing up to class and do the work, because Wednesday wasn’t just the first day of school. It was the easiest.

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