The longest-running coaching rivalry in the NFL is poised for another ferocious instalment on Sunday when the unbeaten Pittsburgh Steelers take on the Super Bowl-chasing Baltimore Ravens.
An AFC North fixture with a history of bruising, hard-fought encounters will be given an added edge by the fact it marks the 25th regular-season meeting between Steelers coach Mike Tomlin and Ravens counterpart John Harbaugh.
Since the two head coaches first faced each other in 2008, Harbaugh holds the edge in victories with 13 to Tomlin's 11.
Tomlin has won two out of three playoff meetings with Harbaugh's Ravens, however, and this season leads a rejuvenated Steelers team who own the last remaining perfect record in the NFL at 6-0.
The 5-1 Ravens, meanwhile, have the chance to end the Steelers unbeaten streak on Sunday, and will go top of the division with a victory.
History suggests another heavyweight tussle is on the cards at Baltimore's M&T Bank Stadium. No fewer than 16 games between the Ravens and the Steelers in the Tomlin-Harbaugh era have been decided by four points or less.
"You know what the Ravens games are about," Tomlin told reporters at a press conference. "They are a top-notch organization and football team. They have talent across the board. They're familiar with us. We're familiar with them.
- 'Rough and tumble' -
"We should anticipate it being a physical and rough-and-tumble game because history tells us that, and how the two teams are playing this year also gives you that indication."
After a relatively disappointing 2019 campaign, where the Steelers finished 8-8 and a distant second to the Ravens (14-2), Tomlin is reveling in being back in what he describes as the "kitchen that is AFC North football."
Harbaugh, meanwhile, speaks admiringly of the Steelers and Tomlin's ability to keep the franchise performing at a relatively high level year-in, year-out. Since joining the franchise in 2007, Tomlin has never had a losing season, taken the team to eight playoff appearances and one Super Bowl victory.
"They stay true to themselves, and that's what they're all about," Harbaugh said of the Steelers.
"So, that's a mark of a heck of a coach, and obviously coach Tomlin is one of the best, and we have great respect for everything they do."
Sunday's game also marks the first head-to-head duel between veteran Steelers quarterback Ben Roethlisberger and Baltimore's reigning NFL Most Valuable Player Lamar Jackson.
Roethlisberger, who missed almost the entire 2019 campaign due to injury, says he's relishing a fixture he described as "football in its purest form."
"I didn't get to play in it last year. I missed this," Roethlisberger said.
"As much as this game hurts physically at the end of the day, you miss this rivalry because this is fun. It's football in its purest form.
"It should be a good matchup. We will have our hands full."
- Bills eye weary Pats -
Elsewhere on Sunday, the New England Patriots head into their divisional scrap with the Buffalo Bills in the unaccustomed position of underdogs.
The Patriots have spent the week licking their wounds after a 33-6 mauling against the San Fransciso 49ers at Foxboro last weekend, the worst home loss of the Bill Belichick area.
More significantly, the defeat was the Patriots' third consecutive loss -- the first time since 2002 the team has suffered three straight defeats.
"We're just not performing at a good level right now in any area," Belichick said after a defeat that left his team at 2-4 and third in the AFC East.
It means the Bills (5-2) can put further daylight between themselves and their divisional rivals with what would be a first win over the Patriots since 2016 at Orchard Park on Sunday.
"It's the most important game because it's the next one," Bills quarterback Josh Allen said. "We're not trying to make it a bigger deal or a smaller deal than it needs to be."
The Patriots' job will be made harder after receiver Julian Edelman was forced to undergo surgery on a sore knee earlier this week, ruling him out of the game.