Super Bowls are supposed to be about the players. But not edition XLVII of America's gaudiest sporting pageant – or at least not until the San Francisco 49ers and Baltimore Ravens actually kick off in the New Orleans Superdome, at 11.30 Irish time tomorrow night.
This time it's been a tale of two coaches. Jim Harbaugh and John Harbaugh are brothers, sons of Jack Harbaugh, formerly one of the top coaches in US college football. Jim, born in December 1963 and the younger of the pair by 15 months, is in charge of the San Francisco 49ers. John is his opposite number at the Baltimore Ravens.
As children they used to share a bedroom. Now not only are they the first pair of brothers to become NFL head coaches, they also find themselves on opposite sides in the league's marquee game. And one of two ferociously competitive siblings will finish the night a loser.
In their playing days, Jim, who spent 14 seasons as a quarterback in the NFL, was the better athlete. John never made it beyond college level, honing his trade instead as a co-ordinator and defensive coach for the Philadelphia Eagles, before moving to Baltimore, where he made the play-offs in each of his five seasons in charge.
In their one head-to-head match-up, on Thanksgiving Day 2011, John Harbaugh's Ravens prevailed in a dour defensive match-up, 16-6.
The brothers both own explosive tempers and both of them are ready to gamble, as they proved in 2012. In Baltimore, John changed the team's offensive co-ordinator three-quarters of the way through the season, sparking a resurgence that resulted in the Ravens averaging more than 427 yards and 30 points over their three play-off games to reach the Super Bowl.
In San Francisco, Jim Harbaugh switched quarterbacks, with no less wondrous results. Colin Kaepernick started 2012 as the back-up to Alex Smith. In early November Smith was injured and Kaepernick, in just his second season, took over as starter.
In his first game in the play-offs, he led the 49ers to a 45-31 victory over the Green Bay Packers and broke an NFL single-game record for a quarterback, with 181 rushing yards. And tomorrow night, Kaepernick and his opposite number Joe Flacco of the Ravens, will take centre stage as the 'Har Bowl' finally becomes the Super Bowl.
Recent Super Bowls have been nailbiting affairs, with four of the last five won and lost on the final drive. But this one could be a whole game to remember, between two teams once best known for their defence but who have broken loose on offence as well. Come Monday, there will be one elated Harbaugh brother. But which?
San Francisco 49ers v Baltimore,
Live, tomorrow, BBC2/Sky Sports 1, 11.30