Richard Sherman v Demaryius Thomas
By now the world has seen Richard Sherman's post-game interview in which he labelled San Francisco wide receiver Michael Crabtree as ''sorry'' and ''mediocre''. Sherman was far more respectful in discussing Denver's Demaryius Thomas, who will command the majority of Sherman's time during the game.
The Stanford graduate, whom many (including himself) consider the best cornerback in the game, usually patrols a side of the field rather than a specific player, but he may go wandering to lock horns with Thomas, the biggest weapon at Peyton Manning's disposal. He is Manning's favourite target, hauling in 92 passes for 1430 yards and 14 touchdowns over the season. He, along with Julius Thomas, Eric Decker and Wes Welker, pose a serious problem for any pass defence, even Seattle's ''Legion of Boom''.
Denver offensive line v Seattle pass rush
The work that the Denver offensive line has put in so far in the playoffs has been utterly brilliant - rendering the pass rush of San Diego and New England useless, and keeping their 37-year-old, surgically repaired quarterback relatively untouched. But neither of those teams are Seattle, and their big men up front are no slouches.
Led by Michael Bennett and Cliff Avril, who combined for 16½ sacks this season, the Seahawks will need to put pressure on Manning following his record-breaking year, in which he picked defences apart at will.
If Seattle can get their hands on Manning early and often, it will go a long way to deciding who wins this game. If No.18 has all the time in the world to drop back and pass, as he did against the New England Patriots two weeks ago, there will only be one outcome.
Peyton Manning v the weather
The theory that Peyton Manning cannot play in extremely cold weather has some weight - his record in games played below
4 degrees is a mediocre 10 wins and 11 losses.
The games that spring to mind are three playoff losses in the early 2000s (twice to Tom Brady and the Patriots, the other a 41-0 hiding from the New York Jets) and the heartbreaker at home against eventual champions the Baltimore Ravens last season, where only a 70-yard pass from Joe Flacco to Jacoby Jones with seconds remaining saw the Ravens force overtime.
The problem for Manning is the sample size, which is small and mostly away games, as he spent most of his career in the comfy confines of a domed stadium in Indianapolis.
That said, it is clear that the better the weather, the stronger the chances for the pass-happy Broncos. The forecast in New York on Sunday is a balmy
13 degrees. If it stays like that, Denver will be feeling pretty good about their chances.
Marshawn Lynch v Denver's run defence
From off-field incidents to a love of Skittles, there's rarely a dull moment with Seattle's running back Marshawn Lynch, but since his now legendary ''Beast Mode'' touchdown in the 2010 playoffs against the New Orleans Saints, Lynch has garnered attention mostly for the right reasons.
Over his past 45 games, no running back in the NFL has as many touches, yards or touchdowns as Lynch - and in an offence where Russell Wilson is more of a game manager than a gunslinger, he is the backbone of the offence.
All eyes were on New England's LeGarrette Blount after he gouged the Colts for 166 yards and four touchdowns in their divisional round match-up. His performance against Denver? Five rushing attempts for a measly six yards. It is totally unrealistic to expect the Broncos to limit Lynch to that number, but if they can hold him to 50 or 60, they'll probably win.
Pete Carroll v John Fox
The teams' two coaches are distinctly different. Seahawks coach Carroll is a brash, outspoken character whose actions on the sideline are loud and visceral.
Fox, on the other hand, is usually quiet and reserved, and is often criticised for his conservative attitude towards the game.
Even now, his decision to order Manning to run out the clock and settle for overtime in that Ravens loss last season is questioned by pundits and analysts.