The Detroit Lions moved into a first-place tie with Chicago in the NFC North thanks to a 40-32 victory over the Bears at Ford Field on Sunday.
Reggie Bush, who missed last weekend's win over the Washington Redskins due to a knee injury, ran for 139 yards on 18 carries, including a 37-yard touchdown run as the Lions (3-1) rallied from 10-6 down early in the second quarter with 24 straight points.
The Kansas City Chiefs improved to 4-0 for the first time in a decade with a 31-7 romp against the injury-depleted New York Giants.
Alex Smith completed 24 of 41 passes for a season-high 288 yards with three TDs as the 2011 Super Bowl champions slumped to 0-4.
Brian Hoyer threw two TD passes in his first home start to guide Cleveland to a 17-6 success against the Cincinnati Bengals.
Hoyer connected with Chris Ogbonnaya on a one-yard score to give the Browns (2-2) an 11-point cushion with 4:54 left on the clock.
London's love affair with the NFL grew ever stronger as Adrian Peterson lit up a sold-out Wembley to lead the Minnesota Vikings to a thrilling 34-27 win over the Pittsburgh Steelers.
The reigning MVP scored two touchdowns and ran for 140 yards as the Vikings prevailed in an enthralling contest between two previously winless teams desperate to save their seasons.
The Seattle Seahawks achieved the first 4-0 start in franchise history courtesy of a 23-20 win against the Houston Texans (2-2), Steven Hauschka's overtime field goal proving decisive.
The Arizona Cardinals overturned a 10-point fourth-quarter deficit to topple Tampa Bay 13-10.
Jay Feely kicked a 27-yard field goal 1:29 from the end to condemn the Buccaneers (0-4) to their third final-minute loss of the season.
Rookie linebacker Kiko Alonso's second interception of the game with 57 seconds left clinched a 23-20 victory for the Buffalo Bulls against the Baltimore Ravens.
Aaron Williams also intercepted Joe Flacco twice - Flacco threw a career-worst five interceptions - while EJ Manuel threw a 42-yard TD pass to fellow rookie Robert Woods to put the Bills in control.
The Jacksonville Jaguars remained winless after Indianapolis stormed to a 37-3 triumph.
Andrew Luck hurled two TD passes while Trent Richardson ran for one score for the Colts (3-1).
Peyton Manning threw for four touchdowns as he led the Denver Broncos to a record-breaking 52-20 win over the Philadelphia Eagles.
Manning was once again at the heart of everything the Broncos did as they scored more points than they ever had before in a single game to improve to 4-0.
Manning completed 28 of 34 passes for 327 yards and found Demaryius Thomas and Wes Welker twice apiece to take his TD total to 16, the most ever in the first month of a season.
The New England Patriots also moved to 4-0 as Tom Brady led them to a 30-23 win over the Atlanta Falcons.
Brady threw for 316 yards and two TDs as the Patriots remained perfect through four for the first time since 2007, when they racked up a perfect 16-0 regular-season record.
Philip Rivers threw for 401 yards and three touchdowns as the San Diego Chargers beat the Dallas Cowboys 30-21.
Dallas were riding high after a 21-point second quarter but Rivers and the Chargers stormed back, including a 56-yard TD pass to Antonio Gates in the fourth which blew the game open.
Jake Locker threw for threee touchdowns before being forced off with a hip injury in the Tennessee Titans' 38-13 victory over the New York Jets, while the Washington Redskins rallied from 14 points down to beat the Oakland Raiders 24-14 for their first win of the season.
Meanwhile, The NFL is discussing expanding the play-offs from 12 teams to 14 while decreasing the preseason schedule to three games per team, ESPN reported on Sunday.
The expanded playoffs proposal would offset teams' lost revenue from eliminating one preseason game, and may add television revenue for the league.
NFL commissioner Roger Goodell said last week the new scheduling format is a possibility, but would not take effect in 2014.
However, ESPN reported the league might implement the format as early as 2014 if it gets the necessary votes from team owners.
The league also needs to establish a new preseason scheduling formula, confirm sponsorship agreements and resolve a few stadium lease issues.
The league's competition committee reportedly recommended the three-game preseason model as the minimum period necessary to evaluate players.