Matt Moore left the game with 2:28 left in the fourth quarter after getting blindsided by Giants defensive end Osi Umenyiora, who raced past left tackle Jordan Gross to sack Moore and force a fumble. Gross alertly picked up the ball and brought it out of the end zone to avoid a touchdown or a safety, but the Panthers lost 31-18 at the New Meadowlands Stadium.
Moore got up on one knee and remained on the field for awhile before walking off alongside the team's trainers to the sideline. He was replaced by Clausen.
Coach John Fox said after the game that Moore did indeed have a concussion, although some others in the organization cautioned it might be a little too early to tell.
If Moore does have a concussion, that could put Moore's status for next week's game against Tampa Bay in jeopardy since he probably won't practice much. That could also mean the Clausen era will start a little earlier than expected. Clausen finished up the game throwing two incompletions under heavy pressure.
Moore finished the game 14 of 32 for 182 yards with one touchdown and three interceptions, all of those coming in the end zone.
"It's a tight window down there, advantage defense," said coach John Fox on Moore's red-zone interceptions. "We'd like to see a couple of different decisions down there but it was unfortunate. We did move the ball fairly well, but those mistakes cost us."
Gross, one of the team's captains, said he felt bad after the game for giving up the sack that led to Moore's injury.
"It's tough," Gross said. "When you're the left tackle and you get beat, bad things happen. When you throw the ball a lot and feel like you've got a pretty good game going and then all it takes is one play and something bad can happen."
LINEUP WATCH: Rookie wide receiver Brandon LaFell got the start Sunday over Dwayne Jarrett, but admitted afterward he played a "horrible game."
"It means a lot to get my first start under my belt and get some reps under my belt, but I have a lot of work to do," said LaFell, who let one pass bounce right off his hands.
LaFell (two catches, 22 yards) did draw a pass interference penalty that set the Panthers up inside the Giants' 5-yard line.
When asked what he wants to get better at, LaFell said, "Everything -- blocking, catching the ball, running the right routes. I played a horrible game. If I would have played halfway better I think we would have had a chance to win this game."
Jarrett was used as the team's third receiver behind Steve Smith and LaFell and made two nice grabs for 40 yards during the hurry-up offense in the fourth quarter. Other than that, he wasn't a major factor in the offense.
BY THE NUMBERS: The Panthers turned the ball over five times on Sunday. They've now turned the ball over a combined 11 times in their last two season openers.
STRATEGY AND PERSONNEL
--PK Todd Carter left the game after his first kickoff with a sore back. If it is a lingering problem don't be surprised if the team looks to re-sign Rhys Lloyd.
--QB Matt Moore was taken to the hospital after the game with a concussion.
--WR Charly Martin suffered a concussion in the game and had to leave after the first quarter.
--WR Steve Smith, who missed all of the preseason, had five receptions for 75 yards and a touchdown.
--RB Jonathan Stewart ran for 206 yards in the last meeting here in December, but was held to 12 yards on five carries on Sunday.
Is it time for Jimmy Clausen to take over? Discuss inside the message boards.