BUFFALO, N.Y. -- The list of quarterbacks the Buffalo Bills have faced since Week 12, for the most part, doesn't exactly jump off the page.

With the exception of Tampa Bay's Tom Brady in Week 14, it's not as if the Bills have faced a murderers' row: New England's Mac Jones (three times), Carolina's Cam Newton and P.J. Walker, Atlanta's Matt Ryan and the New York Jets' Zach Wilson.

Brady and the league's No. 1 passing offense represent the only significant challenge the Bills have faced since cornerback Tre'Davious White was lost for the season to a torn ACL on Thanksgiving night.

The question following his injury was how the secondary would respond to being without one of the best corners in the NFL at a position that lacks depth on the Bills' roster.

While the defense has stepped up and exceeded expectations in White's absence, the team has faced some struggling offenses along the way.

On the horizon is an enormous test as the Bills will travel to Kansas City on Sunday (6:30 p.m. ET, CBS), to take on the Chiefs for the second time this season and for a second straight postseason after losing 38-24 at Arrowhead Stadium in last year's AFC Championship Game.

The Bills defeated the Chiefs 38-20 on the road in Week 5, intercepting quarterback Patrick Mahomes twice. But that was a struggling Kansas City offense and a team that started the season 2-3. That's not who the Bills will see this weekend.

Since then, Mahomes has looked more like his normal self, matching Bills quarterback Josh Allen and throwing five touchdowns in the wild-card round. The Chiefs have lost just twice since that setback against the Bills, and Mahomes finished the regular season ranked among the top five in yards (4,839), passing touchdowns (37) and QBR (62.5).

The challenge ahead has similarities to what the Bills faced in the AFC Championship Game last year, when Mahomes completed 76.3% of his passes and threw three touchdowns to zero interceptions. In that game, the Bills could not stop tight end Travis Kelce and wide receiver Tyreek Hill, who combined for 290 yards and two touchdowns on 24 catches.

To slow the Chiefs down, the Bills will rely on All-Pro safeties Jordan Poyer and Micah Hyde and nickelback Taron Johnson (48.5% completion percentage allowed as the nearest defender, ranking ninth), who have been paramount to the defense's success -- including Hyde's impressive interception in the win over New England on Saturday. Corners Levi Wallace (zero touchdowns allowed as nearest defender since Week 13) and Dane Jackson (team-high six passes defensed during that same stretch) have also stepped up.

It's a credit to defensive coordinator Leslie Frazier's ability to devise game plans without White, and it's one reason he is now in the mix for multiple head-coaching jobs.

"Once we lost Tre'Davious, who was arguably one of our top leaders in the secondary along with Micah and Jordan but on our defense in its entirety, that left a void and we were wondering, you know, who's going to step up?" Frazier said. "Who's going to fill that role both verbally as well as production-wise? And Levi, I mean, he's been terrific as far as helping Dane, communicating with him, talking with him, watching tape with him, really leading the other guys in our secondary that are the next guy up."

Without White, Buffalo allowed the lowest completion (52.5%) and third-down conversion percentage (26.3%) in the NFL and the fewest passing yards per game (134.5) over the final six weeks of the season. While the secondary has overall done its job, the pass rush has also taken on more of a presence for the Bills, with 24 sacks since Week 14 (including the playoff win).

"I think you're seeing the younger guys grow through the course of the season, and understanding with better clarity of what's expected and how we want to do things and make the system theirs," coach Sean McDermott said of the pass rush's emergence.

McDermott also pointed to the leadership of veterans Mario Addison, who suffered a shoulder injury in the win over the Patriots, and the longest-tenured Bill, Jerry Hughes. Their presence will be needed against the Chiefs. Mahomes was sacked only 28 times during the regular season, tied for third fewest among quarterbacks who started 17 games.

The Bills went out this offseason and built the team for this very moment, adding two pass-rushers in the first two rounds of the draft and retaining key pieces, such as linebacker Matt Milano.

All of that is about to be tested.

"Sean approached the team a couple of weeks ago and said, 'You know, this is gonna have to be playoff football. We're playing game to game, we've gotta go out there, and play our best and get wins,'" Hyde said after the win over the Patriots. "And obviously we were able to do that the last couple of weeks ... getting into this game and feeding off each other, just that back-against-the-wall mentality."