LOS ANGELES, UNITED STATES | Josh Allen and Buffalo Bills kept their NFL post-season hopes alive with a nail-biting 20-17 victory over the Kansas City Chiefs on Sunday as Baltimore held off the Los Angeles Rams to move into pole position in the AFC playoff race.

A 39-yard field goal from Tyler Bass with 1min 54sec remaining sealed victory for Allen and the Bills at the Chiefs' Arrowhead Stadium in another absorbing encounter between the two rivals.

The Bills survived a scare on the Chiefs' final drive, when a superbly worked touchdown which saw tight end Travis Kelce toss a lateral pass to send Kadarius Toney racing into the end zone was ruled out for offside.

Instead the score was called back and Chiefs quarterback Patrick Mahomes was unable to move the chains to leave Buffalo celebrating a win that leaves them on 7-6 and second in the AFC East.

Bills quarterback Allen could not hide his relief at the disallowed touchdown that enabled Buffalo to claim a hard-fought victory.

"That might have been the craziest play I've ever seen in my life," Allen said of Kelce's lateral touchdown pass.

"We got a win, we've obviously got some things to clean up, but we'll take it. We just rallied behind each other, played for each other. Wish we'd scored some more points but a win's a win."

Allen threw one touchdown and rushed for another to finish with 233 passing yards from 23 completions.

Opposite number Mahomes had a relatively quiet day, with one touchdown and an interception for 271 yards as the reigning Super Bowl champions fell to a second straight loss.

WALK OFF PUNT RETURN

Elsewhere Sunday, a Tylan Wallace punt return touchdown in overtime sealed a thrilling 37-31 victory for the Baltimore Ravens over the Los Angeles Rams.

Wallace's 76-yard dash for glory helped the Ravens improve to an AFC-best record 10-3, boosting their chances of claiming top seeding in the NFL postseason.

"I'm just happy I was able to make a difference in the game," Wallace said. "You never know when your moment's gonna come, so when it does you just take advantage of it."

The walkoff touchdown was the final act of a wild game that saw the lead change hands eight times in regulation.

The Rams forced overtime with a Lucas Havrisik field goal with seven seconds remaining that tied the score at 31-31 after the Ravens had snatched the lead late in the fourth quarter thanks to a Zay Flowers touchdown and a two-point conversion to make it 31-28.

Ravens quarterback Lamar Jackson finished the game 24-of-43 completions with 316 passing yards and three touchdowns with one interception.

The San Francisco 49ers enhanced their reputation as Super Bowl contenders with a dominant 28-16 win over the Seattle Seahawks in Santa Clara.

Quarterback Brock Purdy threw two touchdowns with 368 yards while running back Christian McCaffrey rushed for 145 yards as the Niners improved to 10-3.

In Las Vegas, meanwhile, the Raiders and the Minnesota Vikings came within a whisker of the first 0-0 scoreline of the NFL's Super Bowl era before Greg Joseph's 36-yard field goal with 1:57 on the clock gave the Vikings a 3-0 victory.

The result was the lowest scoring game since Pittsburgh defeated Miami by the same scoreline in 2007. The last time a game finished 0-0 after four quarters came in a 1943 arm wrestle between the New York Giants and the Detroit Lions.

In other games, the Detroit Lions crashed to an upset 28-13 defeat to the Chicago Bears in their divisional battle at Soldier Field.

Chicago quarterback Justin Fields threw for 223 yards with one touchdown and rushed for an 11-yard solo score late in the fourth quarter to set up the win.

In Cleveland, Trevor Lawrence shrugged off a high ankle sprain to start at quarterback for Jacksonville but had a mixed outing as the Jaguars (8-5) slumped to a 31-27 loss to the Browns, who improved to 8-5.

At East Rutherford, New York Jets quarterback Zach Wilson brushed off his critics with two touchdowns and 301 yards in a 30-6 rout of the Houston Texans.

Texans’ rookie sensation quarterback C.J. Stroud had a day to forget, finishing with just 91 yards and no touchdowns. He was sacked four times and ended up in concussion protocol.