September 30, 2001. Week 3. The old Foxboro Stadium, outside Boston. New England gets its first win of the season against a Colts squad coming off consecutive playoff appearances. Between them, the quarterbacks on the field didn’t crack 400 yards passing and managed only one touchdown pass. Statistically speaking, it's about as nondescript an afternoon as they come. Hindsight, though, makes the day significant for two reasons. First, New England’s Tom Brady, a sixth-round pick out of Michigan in 1999, made his first start for an injured Drew Bledsoe.

Second, it was the first of 14 meetings between Brady and Peyton Manning, both of whom are universally viewed as among the small handful of signal callers in the conversation about Greatest of All Time.

Sunday in Denver (3 pm ET, CBS), it’s Brady versus Manning XV, and this installment is arguably the most significant – not simply because a berth in this year’s Super Bowl is on the line (though that ought to be enough, right?). Rather, in our legacy-and-rankings-obsessed, wildly over-reductive sports culture, Sunday’s result will carry massive weight in the titanic QB-versus-QB debate guaranteed to rage long after both have hung up their cleats.

Brady has a 10-4 advantage in head-to-head matchups, but the pair have split two previous AFC title games. Manning has more yards and touchdowns (and interceptions), Brady more playoff success (and fewer high-profile mistakes).

This head-to-head has all the makings of a classic, but to crack the ranks of the greatest Brady versus Manning games will require something special. Here are our picks for the five best games, in ascending order:

5. 2010, Week 11: Gillette Stadium, Foxborough, Massachusetts – Patriots 31, Colts 28

A true microcosm of the Brady versus Manning debate, and the debate about Manning, generally. The "Peyton Rules!" crowd points to 396 passing yards and four touchdowns, including two in the fourth quarter to someone named Blair White. The "Peyton Chokes!" crowd points to a key interception, courtesy of James Sanders on the New England 6-yard line with 31 seconds to play. Brady, meanwhile, has only 186 yards, but he tosses two touchdowns and completes all but six of the 25 passes he throws.

4. 2013, Week 12: Gillette Stadium, Foxborough, Massachusetts – Patriots 34, Broncos 31 (OT)

This is second meeting between Brady and Manning after Peyton signed with the Broncos following the 2011 season. This time, the Patriots fall behind, going into halftime with a 24-0 deficit that seems too large even for someone of Brady’s incredible skill, experience, and unrelenting handsomeness. But in the third and fourth quarters, Tom Terrific comes alive, completing more than 80 percent of his passes and throwing three touchdown passes as the Patriots score on their first five possessions out of the break. Manning, meanwhile, has his worst game as a Bronco, with a mere 150 yards and an interception.

3. 2003, Week 13: RCA Dome, Indianapolis – Patriots 38, Colts 34

The Colts fall behind in the first half before rallying in front of the home crowd. Manning hits Wayne, Marvin Harrison, and Troy Walters for second-half touchdown passes (three of his four on the day), but midway through the fourth, Brady throws one of his own. Needing a touchdown to win on their final drive, Manning leads the Colts to first-and-goal at the New England 2-yard line. But in a truly epic stand, the Patriots stuff one Manning pass and three Edgerrin James runs to win. Value added for New England: The game goes a long way towards determining home-field advantage in the AFC playoffs, putting Manning in Foxborough for the title game, where he proceeds to throw four interceptions. Note that game is not on this list.

2. 2009, Week 10: Lucas Oil Stadium, Indianapolis – Colts 35, Patriots 34

Manning and Brady each light up the scoreboard like a pinball game: 375 yards and three touchdowns for Brady; 327/4 for Manning. Once again, the Patriots build up a big lead, and once again Manning and the Colts go bananas down the stretch to erase it. But as good as each quarterback performs, it is New England Coach Bill Belichick who dominates the headlines Monday morning, after going for it on fourth and two from his own 28-yard line rather than give the ball back to Manning with just over two minutes remaining. The Colts stop Brady’s pass to Kevin Faulk just short of a first down, and with 13 seconds remaining, Manning hits Reggie Wayne for the game-winning score.

1. 2006 AFC Championship: RCA Dome, Indianapolis – Colts 38, Patriots 34

At the 5:35 mark of the second quarter, Manning telegraphs a throw to the sideline that is intercepted and returned for a touchdown by New England’s Asante Samuel, giving the Patriots a 21-3 lead. More than 60,000 fans at the RCA Dome, well aware of those aforementioned four picks that Manning threw in the ’03 AFC title game against Brady’s Pats, feel a tiny bit of bile well up in their throats. But in the second half, Manning torches the Patriots defense for four touchdown drives, including the one that ultimately pushes the Colts ahead with only a minute to play. An argument can be made for the 2009, Week 10 game being a better overall football game, but keep in mind: The win sends Manning on to his only Super Bowl victory. Considering that many people called this AFC Championship the season's real Super Bowl, the victory is likely the most significant in Manning's career.