Welcome to the AFC Championship Game, where it's a matchup of contrasts: the established powerhouse facing a resilient challenger looking to finally break through with a win against its longtime nemesis.

Seeking an unprecedented Super Bowl three-peat, the top-seeded Kansas City Chiefs are riding an eight-game playoff win streak. Meanwhile the No. 2-seeded Buffalo Bills haven't been to the Super Bowl in more than three decades, and in three of their past four postseason appearances, they were knocked out by the Chiefs.

The Chiefs have had the Bills' number in the playoffs over the past four years, including an epic 2021 AFC divisional-round playoff game in which the Bills were 13 seconds -- no, that's not a Taylor Swift Easter egg -- away from advancing to the AFC championship after Josh Allen's 19-yard touchdown strike to Gabe Davis gave them a three-point lead. But of course, Patrick Mahomes responded, orchestrating a three-play field goal drive to tie it, and one overtime possession later, the Chiefs raucously celebrated an improbable 42-36 win.

Buffalo faced Kansas City again in last year's divisional round, losing 27-24 after Tyler Bass missed a potential game-tying field goal with 1:43 to go. Will this time around be any different?

Follow along for live updates and key insights from the AFC Championship Game below.

Jannik Sinner says the possibility of a doping ban ruling him out of upcoming Grand Slam tournaments did not provide extra motivation to win the Australian Open.

The 23-year-old Italian says he could not have won back-to-back Melbourne titles if he did not have a "clear mind" that he had done nothing wrong.

Sinner was cleared of any wrongdoing by an independent panel after testing positive for banned substance clostebol in April.

The World Anti-Doping Agency (Wada) appealed against the decision and is seeking a ban of between one and two years.

The world number one will have his case heard by the Court of Arbitration for Sport (Cas) from 16-17 April, just over a month before the French Open begins.

Sinner beat German second seed Alexander Zverev in straight sets on Sunday but said the uncertainty around his future did "not really" drive him to win again at Melbourne Park.

"I keep playing like this because I have a clear mind on what happened," Sinner said.

"If I know if I would be guilty, I would not play like this, and that's it.

"I just came off an amazing run again here. I want to enjoy this moment."

In October 2020, former girlfriend Sharypova accused Zverev of violence and emotional abuse during their relationship. Zverev denied the allegations and said they were "unfounded".

Sharypova did not press charges, and a 15-month investigation by the men's ATP Tour found there was "insufficient evidence" to substantiate claims made by Sharypova and so Zverev did not face disciplinary action.

In November 2023, Zverev was given a penalty order and fined by a German court after being accused of physically abusing his ex-girlfriend Patea.

Zverev denied the claims and lodged an objection against the order, which resulted in a public trial.

The trial was discontinued in June 2024 after a settlement was agreed between the defendant and the complainant.

At the time, the court told BBC Sport: "The decision is not a verdict and it is not a decision about guilt or innocence."

The image of Sinner vomiting into a wheelie bin by the side of the court is not one many would expect to mark the start of a new reign of dominance in men's tennis.

But that image, as he battled illness at the China Open in October 2023, has become synonymous with the moment Sinner evolved into a serial title winner.

He would go on to win that match. And that tournament. And most matches he has contested in the 15 months since.

From the start of that tournament in Beijing, Sinner's record is 98 wins and just nine defeats - and three of those losses were against four-time Grand Slam champion and rival Carlos Alcaraz.

Sinner replaced Novak Djokovic as world number one in June 2024 and since then has won a record-equalling 47 of his first 50 matches as the top ranked men's player, matching Bjorn Borg and Jimmy Connors.

He also has a 30-2 record at Slams since winning his first Melbourne title 12 months ago.

Cash said: "Sinner and Alcaraz are so far ahead of everybody else.

"Until other young guys come through it is a two-horse race. We saw that for a while with Roger Federer and Rafael Nadal, then [came] Andy Murray, Djokovic and Stan Wawrinka.

"Things can change really quickly, but as of now it's a one-horse or two-horse race for the Grand Slams."

Wales prop WillGriff John is a major doubt for at least their Six Nations opener against France in Paris on Friday.

The 32-year-old failed a Head Injury Assessment after leaving the field in the first half of Sale Sharks' 32-23 home English Premiership defeat by Bath on Sunday.

John is one of three tight-head props in Warren Gatland's squad alongside Cardiff's Keiron Assiratti and Henry Thomas of Scarlets.

But the number three jersey is problematic for Wales with with Bath's Archie Griffin unavailable following shoulder surgery and Leon Brown having recently retired.

John has not played for Wales since 2021 and, against Bath, was making just his second start for Sale this season with four further replacement appearances.

Assiratti was second choice to Griffin during Wales' autumn internationals and Thomas was an unused squad member as Wales completed 2024 without a win.

Glasgow strengthened their grip on second place in the United Rugby Championship table by grinding out victory over a resolute Connacht at Scotstoun.

The Irish side crossed the whitewash first through David Hawkshaw, but Warriors hit back with tries from Sebastian Cancelliere and Ben Ashfar to lead 17-5 at the break.

Hawkshaw and Cancelliere exchanged further scores in the second half and although Piers O'Conor crossed late on for the visitors, Glasgow held firm to secure the victory.

Franco Smith's side now lead third-placed Bulls by seven points having played two games more than the South African outfit.

With both teams shorn of a raft of internationals before the Six Nations kicking off next weekend, a lack of cohesion was evident for large spells of what was a scrappy contest in difficult conditions.

Having first joined the club back in 2010, Duncan Weir was leading the Glasgow side as captain for the first time and the fly-half banged over a penalty to get Warriors up and running.

Connacht were dominating the exchanges in the opening quarter however, and got their reward when Hawkshaw charged down Ollie Smith's attempted clearance kick before gathering to score.

Henco Venter got Glasgow back on the front foot with a powerful burst and when the ball was whipped wide Cancelliere darted through a gap to go over for Glasgow's first try.

The game was bobbing along without much happening until a majestic show-and-go from prop Fin Richardson saw him slip through the Connacht defence, before offloading to Alex Samuel who sent Ashfar sprinting free to the try line.

Glasgow led by 12 at the break but it was Connacht who struck early in the second half, some neat handling sending Hawkshaw away for his second try of the match.

Having played into a strong breeze in the first half, the Irish side now had the wind at their backs and had an opportunity to reduce the deficit to two points, only for JJ Hanrahan's penalty attempt to come back off the upright.

Warriors gave themselves some breathing space with their third try. Strong carries from Smith and Jack Mann took Glasgow to the brink of the Connacht line before Cancelliere found himself in the right place at the right time again to dot down.

The visitors were not done yet and O'Conor raced over two minutes from time to set up a nervy finish, but Glasgow managed the final moments well to see it out for the win.

British and Irish Lions prop Tadhg Furlong has been ruled out of Ireland's Six Nations opener against England on Saturday by injury.

Furlong, 32, suffered a recurrence of a calf injury at Ireland's training camp in Portugal on Saturday and has returned to Dublin for further assessment.

Connacht's Jack Aungier has been called up to the Six Nations holders' squad as a replacement.

The experienced tighthead prop missed all four November internationals for Ireland with a hamstring issue and only returned for Leinster in their win over La Rochelle three weeks' ago before missing the province's last European game against Bath.

Furlong's absence means Finlay Bealham is likely to start against England at the Aviva Stadium but Ireland's usual third-choice in the position, Tom O'Toole, is suspended for the first two games of the championship.

Hooker Dan Sheehan and wing James Lowe linked up with the Ireland squad on Sunday after returning from injury to play in Leinster's United Rugby Championship win over the Stormers on Saturday.

Sheehan was making his first appearance of the season after sustaining a knee injury in Ireland's summer tour of South Africa while Lowe has been ruled out since sustaining a calf injury in Ireland's final November international against Australia.

The duo's Leinster colleague Jack Boyle also joined up with the squad on Sunday with Connacht scrum-half Caolin Blade also set to arrive in Portugal on Monday.

Bristol: Lane; Heward, Jenkins, Janse van Rensburg, Kavouvou; Byrne, Marmion; Thomas, Oghre, Lahiff; Dun, Owen, S. Grondona, Harding, Mata.

Replacements: Capon, Woolmore, Kloska, Luatua, Heenan, Wolstenholme, Elizalde, Bailey.

Newcastle: Obatoyinbo; Pepper, Hearle, Clark, Stevenson; Connon, Stuart; Brocklebank, Blamire, McCalllum; De Chaves, McDonald Seran, Van der Walt, Lockwood, Chick.

Replacements: Fletcher, Rewcastle, De Bruin, Hawkins, Leatherbarrow, Davis, Wilkinson, Spencer.

Sin bin: Hearle (66 mins)

Referee: Craig Maxwell-Keys

In another blow for Sale, prop WillGriff John was forced off at half time after failing a head injury assessment, ruling him out of Wales' Six Nations' opener against France next week.

They hade been more than competitive in the first half, despite losing five of their first-choice pack to England call-ups, as they sought to extend an 11-match winning streak in their northern fortress.

The forwards powered the ball to within a metre of the posts and when Rob du Preez slung a long pass over the top, Reed showed his finishing ability by stepping inside the cover to score.

Du Preez added a penalty but after Louis Schreuder forced an error at the breakdown, Bath went onto the attack and McConnochie sprinted over out wide to close the gap.

Sale stormed forward again and when Tom O'Flaherty picked up Carpenter's grubber and was held up just short, du Preez picked up and darted over on the blindside, before adding another penalty, to put Sale clear again.

Bath struck back just before the break, with McConnochie again stretching away from the home defence, and Russell's conversion setting the match up nicely for the second half.

Bath were superb in the second 40 minutes, with Russell pulling the strings.

He seemed to have set up Ojomoh for a quick try, but the wing had juggled the ball against O'Flaherty's shoulder to knock on before diving over, with a video review chalking it off.

Eight minutes later, Bath cycled through 20 phases of attacking play and this time Russell's sweeping pass found Joe Cokanasiga and when he was stopped, Ojomoh powered over with two tacklers unable to stop him.

Russell's conversion and subsequent penalty took him past the century mark for the campaign, and then he produced a marvellous piece of quick thinking in a pivotal moment to turn a difficult moment into a 13-point lead.

Reed had shot through a rare Bath gap but when Sale were penalised at the breakdown, Russell quickly kicked the penalty long despite Sale claiming he had not done so from the mark.

Carr-Smith was on the fly-half's wavelength and sprinted the length of the field to kick on and score.

Carpenter barged his way over to make the last couple of minutes interesting but Russell had converted Carr-Smith's try and then added his late penalty to seal the win.