PITTSBURGH -- Pittsburgh running back James Conner participated without limitations when the Panthers opened practice Monday -- just three months after he was declared cancer-free.

Conner took reps with the first-team offense, moving one step closer to the goal he set when he was diagnosed with Hodgkin lymphoma this past December: playing in the season opener against Villanova on Sept. 3.

"Waking up was real exciting ... felt like it was game day getting back on the field," Conner said. "Great feeling all around."

James Conner thinks he can return to the form he had before he was diagnosed with cancer. Charles LeClaire/USA TODAY Sports

Conner went through 12 rounds of chemotherapy treatment over six months, but he remained an active part of the team -- going through offseason conditioning and even spring practice. But back in the spring, he wore a mask when he did drills and was not able to participate in full-contact activities.

During all the treatments, Conner said he never had any doubt he would be back to play football.

"I hit walls," he said. "There were times that I was down, but I never thought once that I was never going to play football again or wouldn't live."

On Monday, he looked like the player of old -- bouncing around to music during warm-ups and sharing words of encouragement with his teammates. Not only was this his first full practice since his cancer diagnosis -- it also was his first full practice since he sustained a season-ending knee injury in the 2015 opener.

"It's great to have James," coach Pat Narduzzi said. "I had one of the players say, 'Coach, don't baby him, he's a man.' We know he's a man, but we've still got to be smart. He had a good day. It's great to get him out here. It's real. He's back 100 percent, and we're looking forward to seeing what he can do better."

Conner said he still has to work on his conditioning, but he expects to be as good as he was before his season was cut short last year. In his last full season back in 2014, Conner won ACC Player of the Year honors and rushed for 1,765 yards and a school-record 26 touchdowns.

"I'm just working hard every day," Conner said. "There's reason for doubt, for other people to be looking and say, 'He might not come back the same,' but I'm just working. I'm taking advantage of every day."