AFC West champions Denver blasted the Oakland Raiders 34-14 in a record-setting show and NFC West winning Seattle strolled to a 27-9 win over the St. Louis Rams as both finished at 13-3 to ensure homefield advantage in their respective conferences.
Edge-of-the-seat dramatics were reserved for do-or-die games on a season-ending Sunday that had 10 teams vying for the last four play-off berths with all four NFC division crowns still up for grabs.
Green Bay's Aaron Rodgers, who had missed the previous seven games with a broken collarbone, heaved a 48-yard touchdown bomb to Randall Cobb with 38 seconds left to lift the visiting Packers to an enthralling 33-28 division-title showdown victory over the Chicago Bears.
The victory gave the Packers (8-7-1) the NFC North title by the narrowest of margins over quarterback Jay Cutler and the hard-fighting Bears, who dropped to 8-8.
On the game-winning play, Rodgers dodged the pass-rushing Julius Peppers and scrambled to his left on a fourth-and eight from the 48-yard line before finding Cobb deep down the middle beyond Chicago's secondary.
It was a most appropriate Green Bay connection, as Cobb was also returning to the gridiron after missing 10 games with a broken leg.
The Chargers found themselves in a play-offs play-in game after last year's Super Bowl winning Baltimore Ravens and Miami Dolphins were defeated in earlier games.
Needing to beat the already play-off-bound Kansas City Chiefs, San Diego rallied to tie the score 24-24 late in the fourth quarter.
A loss by the Chargers would have ushered the Pittsburgh Steelers into the postseason, after their 20-7 victory over the Cleveland Browns.
A Steel City celebration looked in the offing when Chiefs kicker Ryan Succop had a 41-yard field goal try with less than 10 ticks left on the clock for a KC win. He missed wide right.
San Diego summoned some more magic on their first possession of overtime when they converted a fourth-and-two from their own 28-yard line on a fake punt that at first looked like it had produced a fumble run back for a Chiefs' game-ending touchdown.
Nick Novak went on to kick a 36-yard field goal off that possession and San Diego held the Chiefs from scoring to clinch the final AFC berth in the play-offs.
In Dallas, the Philadelphia Eagles delivered a knockout blow to the Cowboys with a 24-22 win in a showdown for the NFC East title.
Back-up Kyle Orton, playing for the injured Tony Romo, was intercepted on the last Dallas drive to deny the home team. Philadelphia's LeSean McCoy ran for 120 yards to capture the NFL rushing crown with a season total of 1,596 yards.
The New Orleans Saints (11-5) secured the last NFC wildcard with a 42-17 rout of the Tampa Bay Buccaneers.
Also earning first-round byes were AFC East champions the New England Patriots (12-4), 34-20 winners over the Buffalo Bills, and the Carolina Panthers (12-4), who claimed the NFC South crown by edging the Atlanta Falcons 21-20.
Next weekend's wild card round will have the Chargers at Cincinnati and the Chiefs at Indianapolis in the AFC, and the 49ers at Green Bay, and the Saints at Philadelphia in the NFC.
The Panthers were first to clinch an NFC division, overtaking the Falcons when Cam Newton hit Greg Olsen with a seven-yard touchdown pass in the third quarter for a 21-17 lead.
Carolina were made to sweat as Atlanta (4-12) mounted a last-ditch drive with less than a minute to go in hopes of a game-winning field goal but after reaching their own 43-yard line, a bad snap led to a 16-yard loss and Carolina got the win.
It marked the first division crown and first trip to the play-offs in five years for Carolina, who set a franchise record with nine sacks of Falcons quarterback Matt Ryan, including four by defensive end Greg Hardy.
Along with the triumphs came the failures. Last year's Super Bowl-winning Baltimore Ravens and the Miami Dolphins both had a crack at advancing with victories.
"That ends it. That stings," said Ravens (8-8) coach John Harbaugh after a 34-17 road loss to the Cincinnati Bengals (11-5). "Credit to the Bengals, the AFC North champs. They were 8-0 at home and that's quite an accomplishment."
Miami (8-8), who were shut out 19-0 last week by Buffalo, lost 20-7 to the New York Jets (8-8).
Jets owner Woody Johnson was elated, saying that embattled coach Rex Ryan would be back for the 2014 season.
"We're going to keep Rex Ryan, and he's going to be our coach next year," Johnson said. "I couldn't be any prouder of this team."
Two games produced some record-setting achievements.
Denver quarterback Peyton Manning, who last week surpassed Patriots quarterback Tom Brady's single season record of 50 touchdown passes, set a record for most passing yards in a season, and the Broncos established a league high for points.
Manning's 63-yard TD pass to Demaryius Thomas pushed the Broncos past the NFL's record of 589 scored set six years earlier by the Patriots. Denver finished with 606 points.
The quarterback's second scoring connection to Thomas, this time a five-yard strike, gave Manning 5,477 passing yards on the season to surpass the record 5,476 yards by New Orleans Saints quarterback Drew Brees in 2011.
Manning's four first-half TD passes gave him 55 this season.
Indianapolis Colts quarterback Andrew Luck and kicker Adam Vinatieri also hit the record book as AFC South champion Indianapolis Colts beat the Jacksonville Jaguars 30-10.
Luck, who took over from Manning as Colts quarterback, threw for 282 yards in becoming the first player in NFL history to top 8,000 yards for his first two seasons.
Vinatieri kicked three field goals and three extra points to move into fifth place on the NFL career scoring list with 2,006 points, passing George Blanda and Matt Stover.