Since 1990, the league has had a rule that prohibits rookies from attending more than one minicamp until after their school has completed final exams.
For most of the league's rookies, this isn't a problem since most schools are on a two-semester academic calendar and are finished with exams by late April or early May, before teams commence their minicamps.
But there are about 15 schools, including Stanford, which Ertz attended, and Oregon State, where Poyer went, that are on quarter or trimester schedules and don't finish final exams until mid-June, after spring camps are over.
"At the end of the day, I was able to get closer to finishing school," said Poyer, who took nine credits this spring and is just 15 credits short of a degree in liberal studies.
"But at the same time, it was tough knowing that a lot of the other rookies were here getting better."
The NFL implemented the rule 23 years ago as a peace offering to the college coaches who were infuriated with the league for opening the draft to underclassmen. The coaches had declared war on the league and were threatening to ban NFL scouts from their campuses.
The NFL, of course, likes to pretend it had altruistic reasons for creating the rule.
"We are trying to avoid interfering with a player completing his final semester at his school," NFL spokesman Greg Aiello said. "The players who want an education should not feel that they are at a disadvantage in competing for an NFL roster spot."
Yet they are, particularly if they are a late-round pick like Poyer or an undrafted free agent.
"Both of those guys are very smart football players and very smart individuals," Eagles general manager Howie Roseman said of Poyer and Ertz. "Obviously, you would have loved to have had them here [for minicamps and OTAs]. But they'll have an opportunity to catch up.
"They were here for the rookie minicamp. And they had an opportunity to come back [to NovaCare] after school ended for a short bit of time and get up to speed. I also think it's going to be very big for them these couple of days [rookie camp] because it won't be as fast as when the veterans come, and won't be as fast as even the rookie camp we had earlier."
Eagles rookies and selected veterans will practice today and tomorrow before the rest of the veterans report on Thursday afternoon. The first full squad workout will be Friday.
"These next couple of days are going to be very important, especially because of all of the [offensive] signals I have to learn," Ertz said. "The next couple of days are going to be huge."
Both Ertz and Poyer flew to Philadelphia right after their semesters ended for a couple of weeks of one-on-one tutoring with their position coaches. But they missed all of the team install in the spring. While their teammates will be seeing things for the second time when camp opens, they'll be seeing them for the first time. Given the pace head coach Chip Kelly has been running his practices, that could be a problem.
"I don't think I'll actually know [how much missing the spring camps set him back] until I get through camp," said Ertz, who did manage to finish up the requirements for his degree in management science and engineering.
"But I don't think it's going to be much of a hindrance. I've worked my butt off, especially in the weight room and on the field. So I don't think it's going to be much of a deterrent in my performance."
As a second-round pick, Ertz is in no danger of not making the team. But his comfort level with the offense will go a long way in determining the amount of playing time he gets this season.
Poyer, on the other hand, needs to pick up the defense quickly and convince the coaching staff there is a place for him in a secondary that gave up a franchise-record 33 touchdown passes last season.
One thing that will help Poyer is that he was a special-teams standout at Oregon State, both as a returner and a coverage man.
"I love playing special teams," he said. "I like being on kickoffs and punts. Returning kicks. I like helping set up that big play for our team.
"Whether it's special teams, defense, nickel or corner, I'm going to find a way to get on this team. I want to contribute to this team's success this season, and I feel I'll find a way."
Center Jason Kelce appreciates the challenge Ertz and Poyer are facing in trying to learn on the run.
Kelce was a sixth-round pick in 2011. That's the year the entire offseason was deep-sixed by a 4 1/2-month lockout. There were no OTAs. Kelce and the other rookies didn't even receive their playbooks until the day they reported for the start of training camp.
And yet he managed to become a Week 1 starter.
"It's going to be tough for them, for the first week especially," he said. "I still remember those first few days. We didn't have any OTAs or the playbook or anything. It was all thrown on us. Your head is spinning. For the first week to 2 weeks, they'll probably struggle a little bit. But I don't want to say they're going to get it right away or they're not going to get it. Everybody's different. I just know it was tough for me."
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