Carolina Panthers coach Ron Rivera on Monday described wide receiver Steve Smith as "highly doubtful" to play in Sunday's pivotal regular-season finale against the Atlanta Falcons because of a sprained left knee.

The (11-4) Panthers earned a playoff spot by beating the (10-5) New Orleans Saints 17-13 on Sunday and would clinch the NFC South division title and a coveted first-round bye with victory over the Falcons, who are 4-10 going into their Monday night game against San Francisco.

Five-time Pro Bowler Smith, who injured his knee during the first quarter against the Saints, had a magnetic resonance imaging (MRI) exam on Monday which revealed a sprained posterior cruciate ligament.

"It's very optimistic as we go forward," Rivera told reporters about Smith's likely availability heading into the postseason. "He will be treated week to week. It was good news considering the alternative."

Rivera said that Ted Ginn Jr. would probably take over in the starting role from Smith, who has had 64 catches for 745 yards with four touchdowns this season.

"It's time for other guys to step up, and they're ready," offensive coordinator Mike Shula said.