5 things to watch as the Chiefs host the Bills in the Divisional round

The fascinating part about this AFC Divisional round matchup between the Kansas City Chiefs (13-5) and the Buffalo Bills (12-6) is that both teams can rightfully claim vengeance to be a source of motivation.

As the loser of the first game between these two, the Chiefs are only a 1.5-point favorite, according to DraftKings Sportsbook. In Week 5, the Bills handed the Chiefs a 38-20 loss — but that followed last season's AFC Championship, in which Kansas City topped Buffalo 38-24.

With both teams highly motivated to control the AFC's throne, this game promises to be incredibly intriguing. One team is fighting to keep the seat — while the other is looking to usher in a new era.

It doesn't get more important than Sunday evening's game. I have five things to watch in this clash of two Super Bowl contenders.

1. The Chiefs playing through their running backs

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In the Week 5 game, the Bills defended the Chiefs very successfully — limiting quarterback Patrick Mahomes to a meager five yards per attempt and only allowing one completion on a pass thrown 20 or more yards downfield.

One reason this made the Chiefs so ineffective was that the running plays the team called in order to counter Buffalo's deeper coverages never had big results of their own. Between running backs Clyde Edwards-Helaire and Darrel Williams, there were just 40 rushing yards on 12 carries — with no carries resulting in more than 10 yards. Early in the game, Kansas City went away from their ground attack — and never returned to it.

At the same time, the running backs were not utilized in the passing game as much as they have been down the stretch. Edwards-Helaire and Williams combined with Jerick McKinnon for just six passes totaling 42 yards — the longest of them an 11-yard screen pass that ended with Edwards-Helaire injured.

With Mahomes' newfound comfort in finding a running back on a checkdown in rhythm — combined with the playoff version of head coach Andy Reid's screen game — we should see bigger passing plays from the running backs that will take advantage of Buffalo's softer coverage.

They should also be more effective running the ball. Not only does McKinnon look like he is on a postseason roll, but also, the Kansas City offensive line is also playing at a higher level than it was during the season's opening months.

2. Getting to — and containing — Josh Allen

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Buffalo quarterback Allen may be the league's most dangerous quarterback when he's on the move. He's shown great accuracy on the run — and as a ball carrier, he is a freight train who is very difficult to tackle.

With that in mind, teams blitz him. He dropped back against a blitz more than any other quarterback in the regular season. In those situations, he only averaged six yards per attempt for a passer rating of just 81.9. Blitzes were effective against Allen because of how teams prepared them.

Sending extra players pushes Allen to trust his instincts and start trying to run — but if the defensive linemen can maintain their rushing lanes, they can strategize to corral him as he tries to escape.

It's much easier said than done — but this year, that strategy has worked against Allen. Four-man rushes can result in Allen escaping to scramble past the line of scrimmage more often; blitzing with gap integrity can stop him before he gets a full head of steam.

3. Patrick Mahomes passing the ultimate Cover 2 test

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For the Kansas City quarterback, the 2021 season has felt almost like being back in school, taking a full semester in "How To Beat Cover 2 Zone." Against the Bills in Week 5, he failed his first big test. But the final exam is worth way more — and he's been studying hard in the last few months.

The Bills represent the final because no team emphasized the softer, two-high safety zone coverages against the Chiefs than they did. In Week 5, they didn't blitz even one time — and consistently had their all-star safety duo clouding each deep half of the field.

It's likely that Buffalo will trust a similar strategy. It'll be up to Mahomes — and his auxiliary weapons — to nail the final.

To get an A, he'll need to show the same willingness to trust the timing and rhythm of the offense as he did during the 9-1 stretch that ended the regular season. That means getting the ball to a receiver in the flat as soon as he knows the deeper patterns are taken. It means that even when the offensive tackles give up the edge, he must trust the interior offensive line so he can step up behind them and continue his progressions.

It could also mean taking the easy five or six yards on scrambles when those opportunities present themselves — something he did in the first game to accumulate 61 rushing yards. That was a career-high.

4. Limiting exposure in man coverage

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When you blitz, you naturally leave your back end in man coverage. There are man-match coverages that can be considered zone — but for the most part, any plan to pressure a quarterback by blitzing will leave defensive backs in one-on-one coverage situations.

When the blitz doesn't get home, and the play is extended, this can become very dangerous — especially against Allen and the weapons at his disposal. Route-running specialists like Stefon Diggs and Cole Beasley can create their separation when needed — but sometimes, it's not about what the offensive player does. Instead, it's about the defender.

In the first matchup, a close game was blown open when safety Daniel Sorensen allowed tight end Dawson Knox to move towards a scrambling Allen. The blown man coverage left Knox wide open down the sideline. The resulting 53-yard scoring play extended the Bills' lead to 24-10.

When defensive coordinator Steve Spagnuolo chooses to blitz, he'll need to utilize players like Sorensen (or linebacker Ben Niemann) as blitzers — or use them in less-exploitable coverage areas. When facing man coverage, Allen is already more confident. The Chiefs don't need to make it any easier.

5. Winning the turnover battle

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In the first matchup, the Chiefs turned the ball over four times — while the Bills didn't lose it even once. One of those turnovers led directly a touchdown, when a pass to wide receiver Tyreek Hill bounced off his chest and into safety Micah Hyde's hands. Another turnover gave the Buffalo the ball in Kansas City territory when kick returner Byron Pringle coughed up a return.

During that part of the season, ball security felt like the Chiefs' biggest issue — and that game might have been when it had the most significant impact.

But in the second half of the season, the Chiefs' turnover differential completely flipped. Meanwhile, the Bills' was good all year — but it's not because they didn't give the ball away. Less than a month ago, Allen threw three interceptions against the Atlanta Falcons.

Taking care of the ball is likely to be a deciding factor in this battle.