Tom Brady and Peyton Manning are slated to face off for the 17th time in their illustrious careers on Sunday in what's expected to be the final chapter of their generational clash.
Many would argue it's the greatest individual rivalry in sporting history, but verifying that claim requires looking at famous feuds in other sports.
Here are three rivalries that are comparable to Brady-Manning:
Lionel Messi vs. Cristiano Ronaldo
In a nearly unprecedented era of offensive talent, Lionel Messi and Cristiano Ronaldo remain in a different echelon than their peers.
Messi is considered by some to be the greatest footballer of all time. The Barcelona star has captured four Ballon D'or trophies and scored at a rate that no one's ever matched. His detractors will immediately note that he's never won a World Cup, although Messi carried Argentina to the 2014 final before bowing out to Germany in extra time. With 296 goals in 329 appearances for Barcelona, seven La Liga championships, and four Champions League titles, few players are accomplished as Messi.
Ronaldo, Messi's lone challenger to the throne, is a stark contrast to his diminutive rival. The Portuguese international became Real Madrid's all-time leading scorer in October, captured consecutive Ballon D'or trophies in 2013-14, and led the iconic club to its 10th Champions League title in 2014.
When Ronaldo joined Real Madrid in the summer of 2009, their individual competition received another layer of subtext. Real Madrid and Barcelona's rivalries are magnified by the pretext of the Spanish Civil War, with Francisco Franco a fervent supporter of Los Blancos during his monarchist regime. Brady-Manning certainly doesn't have the same political implications, but it is an integral part of American culture.
Larry Bird vs. Magic Johnson
Pegged as the rivalry that brought the NBA to the forefront, Larry Bird and Magic Johnson's epic battles were among the eminent contests of the 1980s.
Bird and Johnson's clashes began in college, where the 6-foot-9 point guard steered Michigan State to the 1979 NCAA title over Indiana State. Johnson won two championships (1980, 1982), while Bird would add one (1981) before the Celtics and Lakers squared off in their first of three postseason encounters during the decade.
In one of the greatest series of all time, Bird's Celtics edged Johnson's Lakers in a seven-game epic to win the 1984 NBA Finals. Johnson exacted a measure of revenge one year later, triumphing over Bird in six games. In their third and final playoff encounter, the Lakers emerged over the Celtics in six games, capturing the 1987 NBA Finals.
Bird-Johnson is one of the NBA's greatest individual rivalries, and added to the luster of Celtics-Lakers lore. Similarly, Brady-Manning turned Colts-Patriots and Broncos-Patriots games into appointment viewing for over a decade.
Roger Federer vs. Rafael Nadal
Roger Federer and Rafael Nadal ushered in the golden age of tennis, with Nadal sporting a 23-11 head-to-head advantage.
Considered two of the greatest players ever, Federer-Nadal operated as a duopoly during the game's deepest period. Twenty-one of the 34 matches between them happened in a tournament final, including eight Grand Slam contests. Some rate Federer's 2006 season, where he went 92-5, as the best campaign of the open era.
Many believe the 2008 Wimbledon final - where Nadal emerged victorious in five sets, 6-4, 6-4, 6-7 (5), 6-7 (10), 9-7 - is the greatest match ever played. Federer and Nadal had won 14 of the 16 Grand Slam titles ahead of this classic. Brady and Manning play team sports, and their singular rivalry isn't tested as often as that between the two tennis immortals.