What to watch for when Chiefs host Bills in potential game of the year

Two AFC powerhouses clash Sunday at 4:25 p.m. ET when the Buffalo Bills visit the Kansas City Chiefs. Presented below are six storylines - one for every scoring drive in the fourth quarter or overtime of the playoff classic they staged last January.

Mahomes vs. Allen

Bills-Chiefs will always have game-of-the-year potential because of the wizards at quarterback. Recall what happened down the stretch of their AFC division-round barn burner. Patrick Mahomes and Josh Allen orchestrated 75-yard touchdown drives after the two-minute warning, somehow leaving enough time for the Chiefs to tie the score in regulation and win it following the OT coin flip.

Predictably, they've been superb this season. Here's how Mahomes and Allen stack up statistically through five weeks:

Advanced numbers and the eye test affirm they're a cut above the rest of the league. No passer is as slippery or creative as Mahomes, as he reminded the Buccaneers earlier this month. Allen didn't flinch while being blitzed in his own end zone last week and aired a deep ball that went for a 98-yard touchdown to Gabe Davis.

In four head-to-head matchups (including playoffs), Allen has passed for 11 touchdowns and two interceptions; Mahomes has thrown 10 TDs and two picks. But Allen's relative inefficiency (60.9% completion rate to Mahomes' 71.6%) has hindered the Bills in a couple of losses.

All eyes on Kelce

Tyreek Hill is gone, but Mahomes' connection with tight end Travis Kelce endures. The Chiefs offense ranks third in overall DVOA and fourth in passing DVOA, per Football Outsiders, as Kelce trends toward his seventh straight All-Pro nod.

Kelce tops the NFL with seven TD grabs and leads the Chiefs in targets, catches, and receiving yards. He's found the end zone in four of five games and scored four times Monday night by eluding Raiders defenders in the red zone.

His 87.0 Pro Football Focus receiving grade, which leads qualified tight ends, actually is subpar for him. But Kelce's on pace to shatter his career high in TDs (11) because he's been dominant in short-yardage scenarios.

He's also flexed his versatility. Targeted exactly as often (8.4 times per game) as he was last season, Kelce's lining up wide on a greater share of pass snaps (34.5%) as Mahomes relies less on his nominal wideouts.

Hill led the Chiefs in receptions and yardage last season while combining with Byron Pringle and Demarcus Robinson, his fellow departed positional peers, to catch 17 of Mahomes' 37 TD throws. This year, Chiefs wide receivers have caught two TDs. Mahomes has leaned on Kelce, backup tight end Jody Fortson, and running back Clyde Edwards-Helaire when Kansas City's in scoring range.

Bills defense seeks redemption

Buffalo's secondary, the strength of the league's best defense in 2021, was gashed toward the end of January's playoff defeat. Hill and Kelce broke loose for huge gains on the last-ditch scoring drives that erased Bills leads. Mahomes completed all six of his passes for 69 yards on Kansas City's overtime march to victory.

The Bills have rebounded to peak form. No team has allowed fewer points this season (12.2 per game). They rank second to the 49ers in defensive DVOA. Buffalo defenders have racked up nine interceptions (Jordan Poyer has four) and held four opponents below 200 net passing yards, including Lamar Jackson's Ravens.

Will injuries inhibit them Sunday? Micah Hyde is sidelined for the season, Tre'Davious White's ACL rehab continues, Poyer's missed time with foot and ribs ailments, and rookie cornerback Christian Benford is coming off hand surgery. Mahomes will test the secondary's depth and next-man-up resolve.

Miller makes his mark

On the same day as Bills-Chiefs in January, Von Miller strip-sacked Tom Brady as his Rams advanced to the NFC title game. Miller went on to win his second Super Bowl before he joined Buffalo in free agency.

How has he fared this season? He's disturbed quarterbacks alongside defensive end Gregory Rousseau, whose four sacks tie Miller for the team lead. Except for Kansas City's Chris Jones, no one in the league has recorded more QB hurries than Miller, per Pro Football Reference. This will be his 19th career matchup with the Chiefs, a personal high.

Buffalo defensive coordinator Leslie Frazier likes to rotate his linemen and edge rushers. Miller played 79% of L.A.'s defensive snaps during his Rams stint and up to 90% of snaps at his All-Pro peak with the Denver Broncos. That figure's down to 56% in 2022, but it's doubtful he'll miss important passing downs Sunday.

K.C. in coverage

Kansas City has scored 31.8 points per game this season. That's No. 1 in the league and the club's highest average since Mahomes' 2018 MVP campaign.

Simultaneously, the defense has slipped. The Chiefs finished top 10 in points allowed in 2019, 2020, and 2021 but were 23rd in the category entering this week.

Stout against the run, the Chiefs defense ranks 19th in passing DVOA and has failed to contain star wideouts. Mike Williams, Mike Evans, and Davante Adams all scored against K.C. while surpassing 100 receiving yards. Defensive back Trent McDuffie could return Sunday from his hamstring injury, but it takes a village to curb Stefon Diggs while accounting for Davis' downfield explosiveness.

The Chiefs have only forced four turnovers, though Monday's controversial roughing-the-passer flag deprived Jones of a sack and fumble recovery against the Raiders. Meanwhile, the Bills have been sloppy at times and have lost five fumbles already, which burned them in their narrow loss to the Dolphins.

Race for the No. 1 seed

AFC headway is at stake Sunday. The Bills and Chiefs are the conference's lone 4-1 teams. The winner will claim sole possession of first place plus the tiebreaking edge for home-field advantage in the postseason.

That edge could be meaningful. Buffalo is 3-0 in home playoff contests during the Allen era and 0-3 on the road. The Chiefs finished one game up in the standings on the Bills teams they eliminated the last two postseasons.

Does a rematch await in the conference title game? A mere three AFC squads (compared to seven in the NFC) entered Week 6 with a winning record and positive point differential.

Only Baltimore (3-2) tails the Bills and Chiefs closely. Sunday's winner will create daylight between themselves and the pack.

Nick Faris is a features writer at theScore.