CHARLOTTE, N.C. -- The Carolina Panthers' miserable year took an even darker twist Monday when tests revealed starting quarterback Matt Moore has a torn labrum in his throwing shoulder and will require season-ending surgery.

Moore will undergo surgery in two weeks and be out four to six months, a league source told ESPN NFL Insider Adam Schefter. He is expected to be able to throw again in April.

Moore was injured when Sedrick Ellis drove his right shoulder into the turf on a sack in the second quarter of New Orleans' 34-3 rout on Sunday. In the last year of his contract and after failing to move the Panthers except in their lone victory this season, Moore may have played his last game in Carolina.

But coach John Fox's reluctance to commit to struggling Jimmy Clausen over fellow rookie Tony Pike as Moore's replacement further illustrated his predicament as the Panthers (1-7) flirt with being one of the lowest-scoring teams in NFL history.

"The two quarterbacks on the roster, we'll take a look at them this week and decide who gives us the best chance to win," Fox said.

To make matters worse, the only bright spot for the Panthers this season -- the defense -- took its own hits. Starting middle linebacker Dan Connor is lost for the season after breaking his hip Sunday, and the team has decided not to bring back weakside linebacker Thomas Davis this season from his second major knee surgery in a year.

Fox also confirmed Jonathan Stewart sustained a concussion Sunday and gave no timetable for fellow running back DeAngelo Williams' return from a foot injury.

The Panthers can't seem to hit bottom.

"It's a reflection of the season," linebacker Jon Beason said.

Moore's injury is part of a stunning fall after he finished 4-1 as a replacement last season, leading to Carolina's decision to release seven-year starter Jake Delhomme. Moore threw five touchdowns, 10 interceptions, lost two fumbles and had a passer rating of 55.6.

And he's been Carolina's best QB.

Fox yanked Clausen, the second-round pick from Notre Dame, shortly after he threw an interception that was returned for a touchdown by Jabari Greer Sunday. Clausen has one touchdown pass, four interceptions, two lost fumbles and a 48 passer rating.

Pike, a sixth-round pick from Cincinnati, took over and was 6-for-12 for 47 yards against the Saints.

None of the three QBs led the Panthers into the end zone Sunday, leaving them with 88 points at the halfway point of the season. Failing to reach double digits in points in half their games, they're on pace to score 176 points. That's not far off from the pace that would leave them in the top five for fewest points in a season since the 16-game schedule was adopted in 1978.

None of the QBs were made available to reporters Monday.

"We're just out of sorts a little bit," Fox said. "Whether it be somebody seeing the right read, turning the protection the right way, throwing the ball accurately."

While Fox said signing another quarterback is unlikely because "I'm not sure there's a huge list available right now," he's ready to experiment.

Fox said third-round pick Armanti Edwards, a college quarterback at Appalachian State who had been converted to receiver, would get some snaps at QB in practice this week.

"If we did not bring in another quarterback, he would be the next best emergency quarterback that we have," he said.

The embattled Fox also has problems at linebacker.

Connor was playing well in his first full season as a starter, but will have surgery this week to put a plate and screws in his hip. Davis, who tore his anterior cruciate ligament for the second time in June, was hoping to come off the physically unable to perform list by Wednesday's deadline.

"It's been 5½ months and I think in his best interest I wouldn't want to rush that and risk another injury," Fox said on the decision to place Davis on IR.

Fox indicated Beason, who made the Pro Bowl last season at middle linebacker, would likely move back there with Jordan Senn a candidate to replace him at weakside.

"I did feel rusty going back" on Sunday, Beason said. "There are some things I've got to get cleaned up."

It means more headaches for Fox, who tried to backtrack from a day earlier when he seemed to blame the front office for offseason moves that slashed payroll and left Carolina as the NFL's youngest team.

"That by no means is an indictment of our personnel by any stretch," Fox said. "I like our football team. I wish we were playing better."

Information from The Associated Press contributed to this report.