GREEN BAY, Wis. — Wide receiver Jordy Nelson spent the first day of Green Bay Packers training camp watching his teammates run around, unable to practice because he’s on the PUP (Physically Unable to Perform) list to start out.

Nelson suffered a torn ACL in his right knee that ended his 2015 season prematurely. But it appears that his left knee is now an issue.

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Nelson told media on Tuesday that he recently had an “incident” with his left knee, which he also described as a “hiccup.” He wouldn’t go into details about what happened, insisting it was minor in nature and said he couldn’t put a timetable on his return outside of coming back prior to Week 1.

Could Nelson miss part or all of the preseason? It depends on the severity and timing of the left knee injury.

Packers head coach Mike McCarthy was optimistic about Nelson’s return with the right knee. Now with the left knee, McCarthy said that he believed all six Packers players on PUP — including Nelson — can see time on the field in camp.

“Just talking to [the Packers team doctor], no long-time concerns with that,” McCarthy said. “I’m not concerned about it.

“Jordy’s a pro. He’s diligent and he’s working through it.”

Nelson said the goal is to be out there for Week 1 on the road against the Jacksonville Jaguars, but he also mentioned coming back for part of camp.

“We’ll be ready for the regular season,” Nelson said. “We’re not worried about it. We’re going to work through it inside and continue to progress, and we’ll be ready to go at some point during camp and definitely for the season.”

Nelson was originally slated to return to the field for the start of camp before this left knee “hiccup” happened, so all indications are — Nelson was mum on it, too — that the right knee is in good shape.

“The only timetable is Week 1,” Nelson said. “That’s the only thing we’re worried about.”

Asked how long he can regain his rapport with Nelson, quarterback Aaron Rodgers felt it could happen quickly.

“Probably a couple of days,” Rodgers said. “He’s a special guy. We’re going to need a little time. Just some reps in practice against press coverage and getting off of that and running and catching and making plays. I am confident he’ll get to place where he can play at the beginning of the year.”

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Eric Edholm is a writer for Shutdown Corner on Yahoo Sports. Have a tip? Email him at edholm@yahoo-inc.com or follow him on Twitter!

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