Carson Wentz and coach Doug Pederson are hoping that Wentz will be allowed to practice 11-on-11 again next week. That would move Wentz a solid step closer to his stated goal of starting the Eagles' season opener, Sept. 6 against the Falcons.

But despite how good Wentz might look or feel, or what he might achieve in practice, the calendar is his enemy. Sept. 6 is on the cusp of being a little too early for comfort when it comes to knee ligament grafts, a medical source familiar with pro athletes' recoveries said Tuesday.

Tuesday's  final morning of the training-camp portion of preseason was as confusing as the weather, with the Eagles practicing in bright sunshine, then under ominous clouds. After practice, players signed autographs in heavy rain that pelted the tent erected next to the NovaCare practice fields, in which Pederson and quarterbacks Wentz and Nick Foles held news conferences.

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Wentz and Pederson appeared Tuesday morning on WIP-FM, and they did not take a confident tone toward Wentz's status for Week 1, now just three weeks away. But the tone struck a few hours later seemed a bit different.

"It's going to be close," Wentz said on WIP, which was something he hadn't exactly said before, though the QB has noted on more than one occasion that doctors might overrule him in his quest to start the opener, less than nine months removed from suffering two ligament tears in his left knee.

The radio appearances came before practice. When Pederson and Wentz spoke with reporters after practice, the emphasis was more on a meeting with the medical staff after Thursday's preseason game at New England, which will decide whether Wentz can go back to full practice. (If you've been following this saga, you know that Wentz began camp doing everything, but after the third day of practice, in which he sprinted out and dodged around the pocket in a full-pads workout, suddenly the rehab plan shifted to Wentz's doing team work only in seven-on-drills, when there are no rushing linemen he might trip over.)

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Wentz told reporters he comes out of camp "feeling kind of ready to go, a little bit."

Asked Tuesday how much 11-on-11 work Wentz would need to be ready for Atlanta, Pederson said: "I would say a full week of preparation. You would love to have more. Those are things we'll evaluate come this weekend.

"We'll sit down after this game, get together with our medical team. … We'll discuss the next step in his progression. I'm excited to see where he's at health-wise; he's done a nice job out here already, these last couple of weeks. I'll be curious to see where it goes from there."

So, in terms of being prepared, it would seem that if Wentz goes back to full practice next week, he certainly can be ready for the opener. But obviously, sharpness and timing aren't the key issues. Wentz, asked Tuesday if being allowed to practice 11-on-11 would mean he is medically cleared for contact, said no, and that being cleared for contact would be the final hurdle to returning to play.

"It's getting close," Wentz said. "It's going to be close."

The medical source said strength, agility and neuromuscular control are assessed before a player returns to live action. There has to be no swelling — though Wentz has said that has not been a problem. But studies show ligaments re-tear at a higher rate if an athlete returns less than nine months after surgery; grafts continue to strengthen for up to two years.

Obviously, Wentz isn't going to sit for two years just to be super safe. But his repair was done Dec. 13, and the season opener is a week shy of nine months later. Would, say, waiting another two weeks add much to the safety factor, or would the difference be negligible? There is no clear answer, the medical source said.

"There's been really no secret that it's going to be close," Wentz said, when asked about his remarks on the radio. "Ultimately, it won't be just my call or the coaches' call — it'll come down to what the doctors say, really. … It's a constant communication. We'll see how the 11-on-11 goes and everything, but ultimately, it's not my call. It's going to be the doctors'. Maybe we'll have to interview the docs and ask them."

Wentz's surgery was performed by Dr. James Bradley of Pittsburgh, a nationally renowned knee surgeon and former Penn State defensive back. The Eagles just appointed a new head orthopedic surgeon, Dr. Christopher Dodson, who serves as head team physician for the 76ers.

Wentz said he wants to get back to 11-on-11 and show Pederson that "I look comfortable; I look confident. And I know I will. … The reps I have gotten, in [seven-on-seven] and everything, I feel confident in both my knee and this scheme and offense. … Hopefully, I can just jump right back into where I left off."

Asked if he is more or less optimistic about playing in the opener than he was when camp opened, three weeks back, Wentz said: "It's been about the same. I've been, the whole time, [thinking] it's going to be close. I knew I was going to just worry about it each day, getting better each day and making sure physically my knee was solid each and every day. Trying not to play the 'what if?' game and predict the future because it's out of my control, but I feel about the same as I did."