FLOWERY BRANCH, Ga. (AP) – This week can’t end soon enough for Atlanta Falcons cornerback Kevin Mathis.

The NFL fined Mathis and Philadelphia linebacker Jeremiah Trotter $5,000 each Thursday for their roles in a pregame fight between both teams Monday night.

Both players were ejected before kickoff, but Mathis suffered a far worse setback on Wednesday.

Working in a one-on-one drill, Mathis landed awkwardly on his left knee and tore his anterior cruciate and medial collateral ligaments. The ninth-year veteran also sustained damage to another part of his knee and hamstring.

The injuries are considered career-threatening, but strong safety Keion Carpenter believes Mathis, who turns 32 in April, will return next season.

“I know with all my heart that Kevin will do everything he can to return from this and be just as good a player as he was,” said Carpenter, who missed all of 2004 after tearing his ACL in a summer drill. “Kevin Mathis can still help this team on the field and in the film room. He just can’t do it on the field.”

Atlanta placed Mathis on the season-ending injured reserve list and signed Christian Morton off Washington’s practice squad. Coach Jim Mora indicated Mathis will undergo reconstructive surgery early next week.

“He’s out for the year, unfortunately, more for him than anybody,” Mora said. “Christian will come in and do a good job for us, so we’ve just got to move on. That’s how you do it in this business.”

When the Falcons (1-0) visit Seattle (0-1) this weekend, Allen Rossum is the top candidate to take Mathis’ spot as the No. 3 cornerback and work in nickel and dime situations.

Rossum, however, hobbled off the field at the end of practice Wednesday with a tight hamstring.

Rossum, who did not practice Thursday, is listed as questionable.

Mora indicated the team might wait until Sunday before deciding who will dress against the Seahawks.

Cornerback DeAngelo Hall and reserve safety Kevin McCadam joined Mathis, Carpenter and Rossum in drawing fines for the pregame scuffle. Hall was hit with a $5,000 fine for grabbing an opponent’s facemask and throwing the helmet of the undisclosed Philadelphia player.

Carpenter and Rossum were told to pay $2,500 each for “entering a fight area.” McCadam was fined $1,000.

Defensive tackle Chad Lavalais said he will appeal a $7,500 fine for leading with his helmet as he hit Eagles quarterback Donovan McNabb during the first quarter. Three Eagles, Keith Adams, Jason Short and Mike Labinjo, were fined for entering the fight area.

Mathis was expected to support Hall, the left-side starter, and right-side starter Jason Webster last season, but he exceeded expectations and thrived in the zone coverages designed by first-year coordinator Ed Donatell.

Injuries to Hall and Webster led to 12 starts for Mathis, his most since 2000 with New Orleans, and he ranked second on the team in tackles entering Week 10. Mathis preserved fourth-quarter leads at Carolina and Denver as he helped the Falcons win both games by returning an interception for a touchdown.

The 31-year-old Mathis fell during a routine drill Wednesday. He was covering a receiver near the sideline and jumped to knock down a pass. His leg buckled as he came down, and trainers carried him off the field in a cart.

Mora believes Morton, who played in parts of Week 16 and 17 losses at New Orleans and Seattle last season, will work as the No. 4 cornerback. There appears little chance undrafted rookie Leigh Torrence, who signed earlier this month after his release from Green Bay, would play against Seattle.

AP-ES-09-15-05 1848EDT

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