GREEN BAY, Wis. (AP) -- Jordy Nelson called it a "hiccup." How long Packers fans have to hold their breath remains to be seen.

As his teammates opened practice Tuesday, Green Bay's talented receiver said a minor issue with his left knee contributed to a delay in his long-awaited return. He will have to wait a little longer to return to practice after having missed the entire 2015 season with a torn ACL in his right knee.

That knee, Nelson stressed, feels great.

"Through training this summer, I had an incident with the other knee. Nothing serious. Just something minor. A little hiccup in it," said Nelson, who was forced to watch his teammates run through drills.

"Our end goal is the same," Nelson said. "We'll be ready for the regular season."

Coach Mike McCarthy said he had no long-term concerns about Nelson, either. The Packers had talked about proceeding cautiously with Nelson, anyway.

But Nelson, who doesn't like to talk about injuries, realizes that even the hint of a new potential problem might send panic through the Packers' passionate fan base. He sought to ease those concerns.

"I'm not worried about it. If it was something more serious, I'd kind of be a little nervous," Nelson said. Later, he added, "Again, not the ACL. No one needs to freak out."

Nelson was the Packers' top deep threat when he got hurt in a preseason game 11 months ago. He also displayed an uncanny ability to make tough sideline catches, as if tiptoeing on a high wire. Nelson, paired with Randall Cobb, gave two-time MVP quarterback Aaron Rodgers one of the top receiving tandems in the league.

But the offense took a step back last season, in part because of Nelson's absence. Without a consistent deep threat, defenses played press coverage on receivers.

This preseason, the Packers have an extra week to prepare because they are playing in the Hall of Fame Game in Canton, Ohio, on Aug. 7. Nelson, who is entering his ninth NFL season, is renowned for his work ethic. He's built chemistry with Rodgers over the years.

Rodgers doesn't think it will take that long to rebuild that connection on the field.

"Probably a couple days. He's a special guy. We're going to need a little bit of time, not necessarily game reps but just some reps in practice," Rodgers said.

Like for Nelson to get the feel again of going against press coverage and making the right cut to get open. At his best, Nelson doesn't need a lot of space to make a catch.

"I'm confident that he'll get to a point where he'll be ready to play when we need him," Rodgers said.

Nelson isn't quite as sure about the process of rebuilding timing. Coming back from such a serious injury is new to him. He's trying to stay away from specifying a timetable, other than the regular season opener on Sept. 11 against Jacksonville.

At the same time, he's confident in his preparation. He's in every meeting.

"But mentally I think I'll be sharp," Nelson said. "It's my ninth year with (Rodgers) so it'll just be getting used to seeing the ball again and we'll be able to do that toward the end of camp."

NOTE: LB Clay Matthews said he had not yet been interviewed by NFL officials looking into a media report from January that linked him to performance-enhancing drugs. Earlier this week, the NFL said it found no credible evidence that now-retired Denver quarterback Peyton Manning was provided with human growth hormone or other prohibited substances as alleged in a documentary by Al-Jazeera America last year. Matthews has steadfastly denied the allegation. "But the truth will come out and everything I said when the allegations came out I still stand by, so I just try to kind of put that in the rearview mirror and focus on the season," Matthews said. LB Julius Peppers, who was also named in the report, also stood by an earlier denial. "I'm just trying to focus on camp and getting ready to play games ... not nonsense," Peppers said.