SPARTANBURG, S.C. -- Carolina Panthers receiver Steve Smith was carted to the locker room with a right shoulder injury Monday night, the latest blow to another key player in an injury-filled start to training camp.
X-rays were negative, but general manager Marty Hurney was uncertain how long the four-time Pro Bowl receiver will be out.
However, Smith's agent, Derrick Fox, said Monday that Smith would likely miss at least two weeks and was considering an MRI exam on the injury, according to the Charlotte Observer.
"Steve has a high threshold of pain, and he's in a lot of pain, so something's off-kilter," Fox said, according to the report.
Smith was injured when he got tangled with cornerback Chris Gamble early in the evening workout, held without pads.
Smith crumpled to the turf and grabbed his right arm after a slight collision with Gamble in a passing drill. He took off his helmet and kicked it before walking to a nearby tent, favoring his right shoulder.
Smith was briefly treated before being carted inside, where he underwent X-rays. It wasn't immediately clear if he would be taken to Charlotte to be further evaluated.
He was seen about an hour after the incident in the team cafeteria with his shoulder in a sling, the Observer reported.
Seeing one of the NFL's top receivers wincing in pain produced some tense moments for the Panthers, a week after they lost starting defensive tackle Maake Kemoeatu for the season with a torn Achilles tendon.
Smith had 78 catches for 1,421 yards and six touchdowns last season and is the top target of quarterback Jake Delhomme. Smith, who turned 30 earlier this year, is Carolina's franchise leader with 51 touchdown catches.
The Panthers have little proven depth behind him. The other starter is 36-year-old Muhsin Muhammad. Dwayne Jarrett, who has caught 16 passes in his first two seasons, is the leading candidate to be the No. 3 receiver this season.
Information from The Associated Press was used in this report.