CHARLOTTE, N.C. -- Carolina Panthers wide receiver Steve Smith, who is struggling with a strained left knee, gives a whole new meaning to the term day-to-day.
On Monday, he said he would play in Sunday's divisional playoff game against the San Francisco 49ers. On Wednesday, he determined he was 71 percent certain.
But Thursday, after his second consecutive day of practice, he said there was a setback, and he re-adjusted his chances to 57 percent.
"I think I overdid it," he said after clicking off the reduction in percentage. "Just went down."
Smith sprained the knee in a Dec. 22 game against the New Orleans Saints, and he did not play in the regular-season finale against the Atlanta Falcons.
The 34-year-old veteran is a key figure for quarterback Cam Newton and the Panthers' passing game. He caught 64 passes for 745 yards and four touchdowns this season, a bit off his usual pace, but his presence adds swagger to the Carolina offense.
After Thursday's pronouncement, he was asked if he considered the diminishing statistics a setback.
"If we're on a curve, no," he said. "If we're on a curve grading system, there is no setback. If there's no curve, then it's a setback.
"Just didn't go as well as I thought. It will be all right. A little treatment. I did everything. I just probably overdid it."
When asked his opinion on Smith's status, coach Ron Rivera repeated the party line.
"Fifty-seven percent," Rivera said Thursday. "That's what he told me. But he looked good. He moved around pretty well. He's not his normal self yet, but he was out there. He did things he was supposed to do. We'll see how he feels tomorrow. He came in and felt a little sore.
"When you watch Steve and watch the way he does things, there's a smoothness to his movements and stuff, and it's not quite there yet. It'll be work, and it's just a matter of time."
Tight end Ben Hartsock (knee), running back Jonathan Stewart (knee) and safety Quintin Mikell (thumb) all had full participation in the Thursday practice.