GREEN BAY, Wis. – When receiver Jordy Nelson opted to undergo knee surgery two weeks ago, he did so because he believed he could return in time for the Green Bay Packers’ regular-season opener at San Francisco on Sept. 8.

Nelson had surgery on Aug. 5 to correct what ESPN’s Adam Schefter reported was a nerve issue that has bothered him on and off since college. Two weeks into the recovery, Nelson remained hopeful that he will be ready for the opener. But in his first public comments since the surgery, he offered no guarantees.

“Our main goal is San Fran,” Nelson said. “And that’s just a goal. You never know what could happen. We’ll just continue to go day by day.”

Nelson would not reveal any details about the surgery but said the problem flared up after a practice during the opening week of training camp. He said if had this happened during the regular season, he could have continued to play.

“I said there’s enough time left for opening week, and we felt we’d be able to get in and get out and be ready to go,” Nelson said. “So that was our plan.”

On Monday while the team practiced outside, Nelson went inside the Don Hutson Center to work out with strength and conditioning coach Mark Lovat.

“It’s felt good,” Nelson said. “We’re slowly progressing still. We’ve been able to do different things with different stuff the trainers have in there for us to speed up the process, so it felt good. We’re right on where we thought we would be.”

In addition to Nelson’s absence, the Packers also have been without receiver Randall Cobb (biceps injury), leaving James Jones as the only one of their top-three receivers currently available.