KANSAS CITY - The emotional upheaval that he had endured last week was clearly evident on Sean McDermott’s face on a number of occasions Sunday night.

The first time it flared came when the Bills forced a fourth-down incompletion against Kansas City Chiefs quarterback Patrick Mahomes which secured a thrilling, hugely-needed 20-17 victory for the Buffalo Bills and McDermott let out a primal scream on the sideline.

In the locker room afterward, the Bills’ media team published a video of his post-game speech where he thanked his players for having his back after a scathing expose that called into question far more than his coaching tendencies dropped like a bomb on One Bills Drive last Thursday.

And then when he met reporters, you could see McDermott’s eyes glisten as he addressed the difficult week he and his family had, and how proud he was of his team for rising above everything - including Von Miller’s legal entanglement - to beat the Chiefs for the third consecutive year in the regular season at Arrowhead Stadium.

“Our guys - the staff, the players - steadfast in their focus,” McDermott said. “I couldn’t be more proud of a group, I really couldn’t at this point in the regular season. To a person, they didn’t flinch. They were focused, they supported one another and they supported me and I don’t take that for granted at all. I’m just super proud of those guys and just a super resilient group.”

Bills report card: Buffalo gets colossal break against Chiefs to stay in wild AFC playoff race

In Tyler Dunne’s 20,000-word, three-part series, 25 former players or coaches from McDermott’s time in Buffalo - almost all anonymously - painted a bleak picture of McDermott’s coaching style including his perceived inability to rise up and meet the biggest moments, his relationships with others in the building, and some questionable messaging.

McDermott had to take time out of his schedule Thursday to explain to reporters and the public about one specific anecdote relating to an ill-advised analogy he used in a speech he made back in 2019, and then Friday, he was again peppered with questions pertaining to the stories. All while having to prepare for a game that Buffalo absolutely had to win if it hoped to entertain any realistic chance of staying in the playoff chase.

“Just incredible support this week, in particular the last couple of days for myself, for my family, and that’s what Buffalo is all about,” he said. “Before I came to the stadium, I called my wife, and (she said she) continues to get texts from our neighbors and our friends in Buffalo. Couldn’t be more grateful or thankful for that.”

Without question, this was a glorious victory for the Bills, the kind that could absolutely send them off on a run similar to 2021 when they were 7-6 and finished with four straight wins to capture the AFC East title. That won’t be easy, not with the schedule they have, but at least it’s now possible.

Here are Sal’s Six Points:

1. The defense finally closed one out

Who among you watching this game fully expected Patrick Mahomes to do what he has almost always done during his NFL career - drive the Chiefs to a game-winning touchdown in the dying moments?

He had 1:54 on the clock and two timeouts to work with, and he was going against a Buffalo defense that had already coughed up a lead in the final two minutes of three games this season. Of course this was happening. But then it didn’t, for two reasons.

First, these are not the same Chiefs in 2023 because despite all of Mahomes’ genius, he simply doesn’t have reliable weapons around him and for the sixth time this year, he failed to put up even 20 points. That had happened just six times total in his first five seasons as KC’s starter.

Second, Kadarius Toney’s knuckle-headed offside penalty wiped out his own TD after he had taken a lateral from Travis Kelce and cruised into the end zone with 1:12 remaining in the fourth quarter.

But hey, there was a third reason, too. The Bills played well on defense most of the night and after that TD was taken away, they buckled down and forced three straight incompletions that silenced the stadium and sent Mahomes into a rage as he had to be restrained on the sideline while screaming at the line judge who had made the offside call.

“They went out there, they knew what they had to get done,” McDermott said. “I mean, the thing that's challenging, in addition to going against Patrick, is the field goal kicker (Harrison Butker) is one of the best. I think he's made one from 60-plus already this season, if I'm not mistaken. And so, you’re defending a small window of grass right there and we were aggressive. We were staying aggressive and the guys responded and we got 'em behind the sticks there and the guys closed it out.”

2. Joe Brady needs to work on time management

The fact that Mahomes had 1:54 to work with on that last possession, which could have proved fatal, came about thanks to some weird play-calling by the new Bills offensive coordinator on the series prior.

The Bills caught a big penalty break when, on a third-and-10 from the KC 27, Allen took a sack but was bailed out when Chiefs CB Jaylen Watson was called for a ticky tack illegal contact penalty against Trent Sherfield. With a fresh set of downs and 2:17 on the clock, the obvious call would have been a run which would have taken the clock down to the two-minute warning.

Then, after that stoppage, the Chiefs may have been forced to use their two remaining timeouts. Instead, they used none because Brady called three straight passes, two of which fell incomplete, and only 23 seconds came off the clock before Tyler Bass made what proved to be the winning 39-yard field goal.

McDermott wasn’t about to throw his new OC under the bus, saying that he was OK with staying aggressive because ideally, the Bills wanted a touchdown there and running may have prevented that chance.

“It’s a delicate balance there,” McDermott said. “You’ve gotta know who you’re playing on the other side, too. Are you playing for three or are you playing for seven and trying to make it that type of game? Whenever you’re going against an elite quarterback and an elite offense, you’ve gotta stay aggressive, too. So, it is a balance, I thought the offense did some really good things tonight.”

3. Dawson Knox was back in the lineup

Knox missed five games after wrist surgery, but he was activated off injured reserve and shared time with rookie Dalton Kincaid, which I wasn’t crazy about.

Less of Kincaid on the field is not good for the Buffalo offense and he seemed to be affected by his lost snaps. He had five catches but they went for only 21 yards as he was not a factor at all. Knox caught three for 36 and was nailed for a holding penalty.

Knox’s return also chewed into Khalil Shakir’s playing time and he had just one catch for 12 yards after enjoying some success while Knox was out. In those five games, as the Bills went to a three-receiver set, Shakir caught 17 passes for 335 yards.

The Bills are paying Knox a lot of money - quite frankly, way more than he’s worth - so they aren’t going to keep him on the bench. Brady is going to have an interesting challenge trying to keep all of these players involved.

4. James Cook is really emerging as a key ingredient

Cook had an excellent game as he rushed for 58 yards on only 10 carries and caught five passes for 83 yards and a touchdown. He was responsible for Buffalo’s two longest pass plays (27 and 25 yards) and also had two rushes of 15 and 12 yards.

This is the fourth straight game Cook has gone over 100 yards from scrimmage, the longest streak by a Bills’ RB since LeSean McCoy did it five straight games in 2016.

“He was awesome,” Allen said. “He’s been working hard, probably had his best week of practice this week, been getting more comfortable with him catching passes out of the backfield and he had a lot of opportunities and he took advantage of that.”

Cook has bounced back nicely from his benching in the Denver game after he fumbled on the first play. His confidence is back and he’s running with conviction, but most important is his emergence in the passing game. That’s an area the Bills have lacked for too long with Allen at QB. In the three games with Brady at OC, Cook has 14 catches for 169 yards and two TDs.

5. Josh Allen’s interception changed the game

Allen made several incredible plays against the Chiefs, but they were almost all overshadowed by his egregious interception in the second quarter, a play that flipped the game script and turned what was looking like a Buffalo runaway into the nailbiter that it became.

The Bills were cruising with a 14-0 lead and were on the move again when Allen escaped pressure on a third-and-4 at the Bills 43. Rather than try to run for the first down, or just throw the ball away, he threw across his body toward the middle to Sherfield and Chamarri Conner picked it off at the Chiefs 48.

Just like that, the Chiefs came alive. Mahomes immediately drove them to a TD, and the Bills never really got back into a groove on offense the rest of the game. They managed only two field goals thereafter, but it ended up being enough thanks to the defense.

“Yeah, yeah, can’t make that throw there,” said Allen, who has now thrown an interception in nine straight games. “Gave them points right before the half. From there on out we were able to move the ball, we just weren’t finishing.

“Thought we were hurting ourselves a little bit with decision making, with penalties, all of the above so we got to tighten it up. Again, that’s a really good team we just played, it’s a really good defense. They figured some stuff out and we’ve got to counter and find a way to keep going.”

6. The Bills have a punting problem

Sam Martin stepped into a difficult situation last season when he was signed at the end of training camp following the release of rookie Matt Araiza. Martin went on to have a solid year and earned himself a new three-year, $6 million contract.

That’s not looking too prudent this season. Martin has followed up with a poor season and in this game, he had a terrible 34.3 net average on four punts. His worst came on the first play of the fourth quarter, a weak 40-yarder that floated right down the middle with inadequate hang time and led to a 25-yard return by Richie James.

With a drive start at the KC 41, Mahomes drove the Chiefs to a tying field goal. The Bills can get out of Martin’s contract after this season with negligible dead cap money and if he doesn’t start punting much better, that would be a wise move.

Sal Maiorana can be reached at maiorana@gannett.com. Follow him on Twitter @salmaiorana and on Threads @salmaiorana1. To subscribe to Sal's newsletter, Bills Blast, which comes out twice a week during the season, please follow this link: https://profile.democratandchronicle.com/newsletters/bills-blast

This article originally appeared on Rochester Democrat and Chronicle: Bills rally around Sean McDermott after tumultuous week to beat Chiefs