Is this the end for No. 4?

If Brett Favre's career ends after Sunday's monster hit the aged quarterback absorbed on his very first pass, he'll go out the way a lot of fans will remember him. Limping off after an interception - his 18th of the year.

On the first series of the game against Buffalo on Sunday, Favre was crushed by Bills linebacker Arthur Moats, knocking the 41-year-old Vikings quarterback out of the game with an injury to his throwing shoulder.

Favre was blindsided by Moats and was slow to get up, then staggered to the sideline. He later walked to the locker room with athletic trainer Eric Sugarman.

Significantly, the guy who owns the NFL record for starting in 297 consecutive regular-season games returned to the sideline later in the second quarter and had a long conversation with interim coach Leslie Frazier and backup Tarvaris Jackson. It appeared Favre was going to come back into the game, but Frazier stuck with Jackson.

Favre watched from the sideline with his arms folded, talking to Jackson after each series. He occasionally wound his throwing shoulder slowly to try and loosen it up. It's been a difficult year for Favre, who has struggled with a sore shoulder, tendinitis in his elbow, two broken bones in his ankle, and 10 stitches in his chin from a hit against the Patriots earlier this year.

He also entered the game 30th in the NFL in passer rating, a far cry from his 33-touchdown, seven-interception performance in 2009 that helped the Vikings reach the NFC title game.

Given Frazier's obvious interest in getting ready for next season, it's not a stretch to say Favre may have thrown his last pass. And interception.

Unwanted record

The Detroit Lions (2-10) have lost an NFL-record 19 straight within their division, the NFC North, the longest such skid since the 1970 merger.

Punchless Arizona

The Cardinals didn't score a touchdown for the second game in a row and have just one in their last three contests - on the final play of a 31-13 loss at Kansas City.

SD streak ends

The Chargers' streak of 18 straight December victories - which tied an NFL record for most victories in any month - came to a thudding end with a 28-13 loss to visiting Oakland. The Chargers' last December loss was on Dec. 31, 2005. San Diego tied the 1970-74 Miami Dolphins, who won 18 straight November games.

Crystal-balling

Expect Jon Gruden to be the coach in San Francisco next season. People close to the former Tampa Bay and Oakland head coach say he is interested in any of three jobs: Dallas, Denver, and the 49ers.

But the Cowboys will stick with Jason Garrett, who at least has the team playing tackle football again, unless Mike Holmgren suddenly becomes available.

And Broncos owner Pat Bowlen already has said he will stick with Josh McDaniels one more season.

Things change, but right now Mike Singletary being fired in San Francisco seems 99 percent certain, and a big name like Gruden is what the Niners need to return to their glory days.

One more time

The New York Jets signed veteran receiver Laveranues Coles to his fourth stint with the team. The Jets had an open roster spot after safety Jim Leonhard was placed on injured reserve Saturday with a broken shin bone.

Contact staff writer Don McKee at dmckee@phillynews.com.

This article contains information from the Associated Press.