The Green Bay Packers and Houston Texans clinched their divisions, while the Baltimore Ravens earned a playoff spot despite another lousy loss.
The jumbled NFC East? Well, that will come down to the final week of the season.
The New York Giants were humiliated 34-0 by the Atlanta Falcons on Sunday, falling into a first-place tie with the Dallas Cowboys and Washington Redskins, who both won to improve to 8-6.
The Redskins did it without Robert Griffin III, who sat out with a sprained right knee and wasn't happy about having to stand on the sideline and watch his teammates play. But fellow rookie Kirk Cousins stepped in and threw for 329 yards and two touchdowns, leading Washington to its fifth straight win, 38-21 over the Cleveland Browns.
"We're in first place in our division now, and it was a great business trip for us," Griffin said. "I got healthier by not playing, we won the game and put ourselves in position to control our own destiny."
Cousins connected with Leonard Hankerson for both TDs in his first career start and the Redskins barely missed a beat without the talented and multi-dimensional RG3. Last week, Cousins came off the bench after Griffin got hurt, and delivered a performance in this one that extended Washington's longest winning streak since 2007.
"I talked to him about being cool, calm and collected and not to freak out," Griffin said. "He did a good job of staying poised and staying confident in there."
Rookie Trent Richardson had a pair of TD runs for the Browns (5-9).
At Arlington, Texas, Dallas' Brandon Carr intercepted a pass by Ben Roethlisberger in overtime, returned it 36 yards to the 1, and Dan Bailey kicked a 21-yard field goal for a 27-24 win over Pittsburgh.
"Those are the plays you dream about in the backyard, making the game-winning interception or touchdown," Carr said.
Bailey's kick — 1:24 into OT — won a game for the second straight week since Dallas practice squad linebacker Jerry Brown was killed in a one-car accident that led to manslaughter charges against teammate Josh Brent. After Carr's interception, Tony Romo took a 2-yard loss to put the kicker in better position for the Cowboys.
The Steelers (7-7) lost for the fourth time in five games and trail AFC North rival Cincinnati by a game for the conference's second wild-card spot. They host the Bengals next week. Roethlisberger is 0-2 since returning from a three-game absence with shoulder and rib injuries.
"There won't be any quit from us, especially from me," Roethlisberger said. "This one is going to sting real bad. It will hopefully make me and make us better."
At Atlanta, Matt Ryan threw three touchdowns passes in a 34-0 win and the Falcons' defense handed the Giants their first regular-season shutout since 1996.
"We love the haters, man," said Falcons cornerback Asante Samuel, who had the first of two interceptions against Eli Manning. "The haters keep us going. So keep your hate coming. We love it. It makes us play with a chip on our shoulder."
Julio Jones caught a couple of scoring throws from Ryan, who broke his own franchise records for completions and passing yards in a season. He finished 23 of 28 for 270 yards.
The Falcons (12-2), who have already clinched the NFC South, moved a step closer to home-field advantage throughout the conference playoffs.
Manning had his lowest-rated game since 2007 for New York (8-6), which went 0-for-3 on fourth down and missed a short field goal.
"Atlanta was very, very good. We were very, very bad," New York coach Tom Coughlin said. "There's no excuse for what happened here."
PACKERS 21, BEARS 13
At Chicago, the Packers clinched their second straight NFC North title with a victory over the archrival Chicago Bears.
James Jones caught all three touchdown passes thrown by the Packers' Aaron Rodgers. Green Bay has now won six straight in the NFL's oldest — and fiercest — rivalry. The Packers (10-4) have won 12 straight against NFC North opponents, the longest streak in the NFL.
Brandon Marshall had a 15-yard TD catch for the Bears (8-6), who have lost five of six and are in danger of missing the playoffs after beginning the year 7-1.
TEXANS 29, COLTS 17
At Houston, Andre Johnson had 151 yards receiving and a touchdown, Bryan Braman scored on a blocked punt and Shayne Graham kicked five field goals to clinch the AFC South for the second straight year.
J.J. Watt had three sacks for the Texans (12-2) as Houston's defense got back on track a week after a 42-14 loss to New England.
The Colts (9-5) had won three straight and needed a win to clinch a playoff berth a year after going 2-14.
BRONCOS 34, RAVENS 17
At Baltimore, Chris Harris returned an interception 98 yards for a momentum-turning touchdown, and Denver won its ninth straight.
Peyton Manning threw for 204 yards and a score in his ninth consecutive win against Baltimore, the first with the Broncos (11-3).
The Ravens (9-5) were playing their first game under offensive coordinator Jim Caldwell, who replaced the fired Cam Cameron. Baltimore clinched a playoff spot by virtue of Pittsburgh's overtime loss to Dallas.
49ERS 41, PATRIOTS 34
At Foxborough, Mass., San Francisco earned a playoff berth by withstanding a stunning comeback by Tom Brady and New England from a 28-point deficit to beat the Patriots.
Michael Crabtree took a short pass from Colin Kaepernick and sped around cornerback Kyle Arrington for a 38-yard touchdown with 6:25 to go, then David Akers made a 28-yard field goal to clinch it. San Francisco (10-3-1) owns at least a wild-card spot and plays at Seattle next week with a chance to win the NFC West.
AFC East champion New England (10-4), which had won seven in a row, trailed 31-3 at one point and lost for the first time at home in December in 21 games. The Patriots also had won 21 in a row in the second half of the schedule before San Francisco somehow regrouped late in a game it seemingly had clinched long before.
VIKINGS 36, RAMS 22
At St. Louis, Adrian Peterson ran for a season-best 212 yards, including an 82-yard touchdown.
Peterson has 1,812 yards rushing for the Vikings (8-6), leaving him 294 shy of breaking the NFL's single-season record of 2,105 by Eric Dickerson of the Los Angeles Rams in 1984. Peterson, less than a year removed from a serious knee injury, has two games left — at Houston and home against Green Bay — to top Dickerson.
The Rams fell to 6-7-1.
SEAHAWKS 50, BILLS 17
At Toronto, Seattle rookie quarterback Russell Wilson ran for three touchdowns and threw for another in leading the Seahawks to their second straight rout.
Wilson scored on runs of 14, 25 and 4 yards and then hit Zach Miller for a 4-yard touchdown in helping the Seahawks (9-5) score 31 points on their first five possessions. The defense forced three consecutive turnovers to start the second half, including Earl Thomas scoring on 57-yard interception return.
The Bills (5-9) were knocked out of playoff contention for a 13th consecutive season.
CARDINALS 31, LIONS 10
At Glendale, Ariz., Greg Toler returned an interception 102 yards for a fourth-quarter touchdown as Arizona ended a nine-game losing streak.
The Cardinals (5-9) intercepted Matthew Stafford three times, returning two for touchdowns and setting up a TD with the other.
The Lions (4-10) lost their sixth straight. Rashad Johnson brought back a pick 53 yards for a touchdown to cap Arizona's 21-point second quarter. Patrick Peterson's interception set up another score.
Detroit's Calvin Johnson became the first player in NFL history with consecutive 1,600-yard receiving seasons and tied an NFL record with his seventh straight 100-yard receiving game.
PANTHERS 31, CHARGERS 7
At San Diego, Mike Tolbert scored twice against his former team and DeAngelo Williams turned a tipped pass from Cam Newton into a 45-yard touchdown reception.
Carolina (5-9) won consecutive games for the first time since last December. The loss knocked the Chargers (5-9) out of playoff contention for the third straight year, and clinched their first losing season since 2003, when they were an NFL-worse 4-12.
SAINTS 41, BUCCANEERS 0
At New Orleans, Drew Brees passed for 307 yards and four touchdowns, and New Orleans posted its first shutout since 1995.
Brees connected on his scoring passes with tight end David Thomas, running back Darren Sproles and receivers Lance Moore and Joe Morgan. Mark Ingram added an 11-yard touchdown run for the Saints (6-8).
Josh Freeman endured one of his worst outings of the season for Tampa Bay (6-8), throwing four interceptions and losing a fumble.
DOLPHINS 24, JAGUARS 3
At Miami, the Dolphins (6-8) kept former teammate Chad Henne out of the end zone, made three fourth-down stops deep in its own territory and benefited from an odd penalty.
The Dolphins turned back three scoring threats, and a go-ahead touchdown for the Jaguars (2-12) came off the board because of an illegal-substitution penalty.
RAIDERS 15, CHIEFS 0
At Oakland, Calif., Sebastian Janikowski kicked five field goals and Darren McFadden rushed for 110 yards.
The Raiders (4-10) overwhelmed the Chiefs (2-12) to snap a six-game losing streak.