GREEN BAY, Wis. — Jordy Nelson's return to practice was greeted with big cheers as the Green Bay Packers got one of their big playmakers back.

At least for a little bit of practice.

Nelson, who missed all of last season with a knee injury, was limited to individual drills Monday and primarily ran routes on air and caught passes from Aaron Rodgers and rookie backups Joe Callahan and Marquise Williams. His goal is simple in his long-awaited comeback: Be ready to play this year's season opener on the road against the Jacksonville Jaguars on Sept. 11.

"Obviously, there's prep that goes into the season with the training camp," Nelson said, "but the important stuff is the games, when it really matters."

The Packers activated Nelson, entering his ninth year, from the physically unable to perform list last week after he had been out with an injury to his other knee.

After keeping his nose in the playbook and paying close attention to the tendencies of defensive backs as he watched practice while he was sidelined, Nelson doesn't feel the missed time on the field will be detrimental.

"I felt better today, honestly, than what I thought I was going to be, wind-wise, conditioning-wise, of running those routes and being full padded and everything," Nelson said. "So I thought that was a good sign."

He acknowledged with a laugh that his cameo work on the field Monday hardly constituted a practice. But that was good enough for those seated in the nearby bleachers as they cheered every catch by Nelson, who participated in warmups with the team before Green Bay's preseason game Thursday.

"Yeah, obviously, the fans are excited," Nelson said. "I'm excited to be back out there practicing and getting ready for Week 1."

Nelson, who tore the ACL in his right knee in a preseason game last summer at Pittsburgh, doesn't know if he will be cleared to play any of the Packers' remaining two exhibition games. That includes Friday night at San Francisco, where Rodgers could get his first preseason action.

"We're progressing," said Nelson, then adding, "It's a fluid situation of how everything reacts and how we feel."

While Nelson being on the field was big news, the Packers solidified another significant development with their offence. Coach Mike McCarthy announced before practice that JC Tretter earned the starting spot at centre over incumbent Corey Linsley, who is on the PUP list because of a hamstring injury.

"JC Tretter has had an excellent camp," said McCarthy, who alluded to Linsley's prolonged unavailability this summer as a factor in the decision.

Tretter, who has been working with the first-string offensive line since the first day of training camp, took the news in stride after he was informed by the coaches Monday morning.

"It'll be a great opportunity, but I don't think the mindset really changes much," said Tretter, a fourth-year pro. "It's just continue to grind away and continue to do what you can to get better every day."

NOTES: Starting S Morgan Burnett (back) remained sidelined. Micah Hyde started the first two preseason games with Burnett out. Brett Hundley, the Packers' top backup quarterback, didn't practice Monday after he aggravated an ankle injury in Thursday's game. Backup G Josh Walker (knee) also was out. Second-year LB Jake Ryan returned to practice after being sidelined since early August with a hamstring injury. ... The Packers released first-year G Matt Rotheram and undrafted rookie long snapper Jesse Schmitt. Rotheram (biceps) and Schmitt (broken hand) suffered injuries earlier in the preseason.

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