So for the first time since the new coach was hired in January, reporters will get their first glimpse of a Kelly-run practice, some of his schemes and what he may have in store at quarterback and other positions.
"It's going to be fast, that's no secret," Maclin said last week. "So I advise you guys not to blink. . . . There's going to be a lot of guys flying around. I think you'll see a bunch of people in different positions, and that's the joy of this offense. I could play every position on the field."
All eyes will be on the quarterbacks at some point during practice. Kelly said last month that his signal callers were "even" on the depth chart, but Maclin said that Vick was running with the first team and that Foles was "sprinkled in" with the starters.
The competition is far from complete, though, and there was another combatant tossed into the mix when the Eagles drafted Southern Cal's Matt Barkley in the fourth round. Barkley spent the weekend working out with other rookies during a three-day minicamp.
Coaches can tell fairly early on - even with the players practicing in shorts and without pads - if a prospect has what it takes to at least compete at this level.
There will be plenty more to observe, if one can keep up. Kelly runs his practices at a fever pace. The offense is expected to be up-tempo, but will it bear any resemblance to the spread offense Kelly ran at Oregon? It's unlikely the coach will reveal much schematically.
Coordinator Bill Davis' defensive plan has been a mystery. Kelly has been noncommittal about what kind of front seven will be employed on base downs, but offseason moves have suggested that the Eagles will primarily have a 3-4 look on the defensive line.
It's a long way until the season opener in September, but it's always interesting to see how the early depth chart stacks up. Kelly said last month it was more of a seating chart at this point, but Monday's first-teamers could give an indication of how certain positions stack up.
Such as: Who's starting at cornerback? Are free-agent acquisitions Cary Williams and Bradley Fletcher with the first team? What about safety? Patrick Chung should get the early nod, but is Nate Allen still a starter?
On offense, there aren't as many question marks, aside from quarterback. There is some uncertainty about what Kelly will do at tight end. He added the versatile James Casey in free agency and drafted Zach Ertz in the second round. What does that mean for Brent Celek and Clay Harbor?
DeSean Jackson and Maclin appear to be locked in at receiver. But does Kelly have a different take on the position?
"He wants a guy to be a complete football player," Maclin said. "He wants a receiver to understand not only his position, but every other position on the field."
Contact Jeff McLane at firstname.lastname@example.org. Follow on Twitter @Jeff_McLane.