Football gods were very kind in delivering us Peyton Manning-Tom Brady rivalry

The first time Tom Brady started an NFL game, he walked off a winner at Peyton Manning's expense, guiding the previously winless New England Patriots to a 44-13 home upset of the defending AFC East champion Indianapolis Colts.

Eleven years and a dozen meetings later, in a vastly superior stadium on that same plot of land in Foxborough, Mass., Brady and Manning will go head-to-head again, each quarterback having staked his claim as the best of his era – or, perhaps, any era.

If Sunday's showdown between the Pats and the Denver Broncos, Manning's new team after 14 seasons in Indy, turns out to be the final clash between these fierce competitors and worthy rivals, let's all give thanks that fate (or, as some call it, the NFL's scheduling formula) has brought them together so frequently.

And if facing off against an equal and opposite force brings out the truest measure of excellence in an all-time great athlete, as it did for Magic Johnson and Larry Bird, then Manning and Brady should also be grateful their respective journeys have been so intertwined.

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On some level, I believe they love and cherish this. Though each man is maniacal enough about winning that he'd probably name JaMarcus Russell as his optimal opponent on any given Sunday, Brady and Manning also understand their places in the football stratosphere, and how cool it is that they ride alone in the front seat of the lead convertible in the 21st century's parade of gridiron greats.

Each future Hall of Famer has found reason to emulate the other while stubbornly clinging to his own, signature style. There is mutual admiration and respect, but neither man is about to concede that his way is not the best way.

So often, one man is in the other's way on a potential path to a championship – that's just the way it is – and we shouldn't take this for granted.

Sometimes, fate deprives us of dream matchups to an almost sadistic degree. Hall of Famers John Elway and Dan Marino were friends and rivals who entered the league together in 1983 but met just twice in careers that each lasted more than a decade-and-a-half.

We were a bit luckier when it came to Elway and Joe Montana, whose San Francisco 49ers throttled Elway's Broncos, 55-10, in Super Bowl XXIV. The two all-time greats went 3-3 against each other in six career meetings, culminating in a Monday Night Football classic at Mile High Stadium in October of 1994.

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That memorable game featured masterful displays of fourth-quarter magic from two of the most clutch players in NFL history. Montana, in his final NFL season (and second with the Kansas City Chiefs), engineered a drive that gave his team a 24-21 lead with 4:08 to go in the back-and-forth affair. Elway's four-yard run with 1:29 remaining put the Broncos on top by a 28-24 margin. Montana responded by completing seven-of-eight passes on a 75-yard march that he managed the clock to perfection, producing the winning points on a five-yard pass to Willie Davis with eight seconds remaining.

When the Broncos and Chiefs staged a rematch at Arrowhead Stadium later that season, Elway and Montana each sat out with injuries, with Hugh Millen and Steve Bono serving as their respective stand-ins. It was as if the football gods insisted that the two comeback kings not spoil their fantastic finale.

With Brady and Manning, the narrative has seldom been so cut-and-dried. The storylines have taken so many turns that bringing up the once commonly accepted conventional wisdom of years past (Bill Belichick is in Manning's head; Brady is the ultimate team guy while Manning is all about individual stats; Brady is an eternally cool field general while Manning is a prickly perfectionist) makes them seem almost laughably outdated, as if we were reciting platitudes from a cold-war manifesto.

It's true that Brady won his first six meetings against Manning, including a pair of piercing playoff conquests, and captured three Super Bowls before the man who would become the league's only four-time MVP got his first and only ring.

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Manning, however, has won four of the past six showdowns, including the Colts' epic comeback triumph in the 2006 AFC championship game that preceded his Super Bowl victory.

After that wild night in Indy, all the old assumptions exploded. Brady came back with perhaps the best-ever statistical season by a quarterback in 2007 to earn his first of two regular-season MVP trophies but lost the Super Bowl in dramatic fashion to Peyton's kid brother, Eli, and the New York Giants, a disappointment that was duplicated last season.

Peyton, meanwhile, proved to be the one in Belichick's head – at least, that's what it seemed after the New England coach's notorious decision to go for it on fourth-and-2 from his own 28-yard line with a six-point lead and just over two minutes remaining in a 2009 Sunday night game against Indy because he feared punting the ball back to Manning.

Each quarterback has come to grips with his football mortality: Brady after a severe knee injury on opening day ended his 2008 season, Manning after a series of neck surgeries forced him to miss the entire 2011 campaign and led Colts owner Jimmy Irsay to release him last spring. Among the nice touches in a friendship that has grown in recent years is the emotional support each quarterback extended to the other during those vulnerable times.

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As the stereotypes have continued to dissolve – Brady, for instance, can be every bit as punitive toward underperforming teammates as Manning – we've come to discover that the two quarterbacks are more alike than different, a pleasant development given that in this era, at least, they have no equals.

So, who's greater? That's fun to debate, but at this point it's almost incidental. Both men are in the very short best quarterback of all-time conversation – with Montana, Elway, Marino, Johnny Unitas, Otto Graham, and perhaps a couple of others – and they always will be.

At this point, it kind of comes down to personal preference. Just as I believe Brady had the superior turn as Saturday Night Live host – and I am oddly in the minority on this, for whatever reason – some may prefer Manning's astounding body of work on the football field to that of his chief rival. There is, however, no conclusive answer, and that's just the way it is.

A little more than two-and-a-half years ago, as Manning was closing in on what most assumed would be a second Super Bowl title in four seasons, an alarming amount of experts prepared to decree that he was the best passer of all time. In the days leading up to the Colts' surprising Super Bowl XLIV setback to the New Orleans Saints, I argued that such a declaration was premature, pointing out that a case could be made for Brady over Manning as the best of this era. (Montana, for what it's worth, agreed.)

Then, last year, the Colts went from perennial playoff participants with Manning to the worst team in the league without him, adding fuel to the assertion that no quarterback has ever been more valuable than No. 18. Indy's dramatic decline, along with the fact that the Patriots managed to go 11-5 with Matt Cassel filling in for Brady in '08, created a Manning is the greatest argument I have found it extremely difficult to rebut.

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Basically, they're both "The Greatest," and I'm more confused than ever.

On Sunday, whatever happens in Foxborough, I don't want to think about any of that. I just want to savor the 13th, and perhaps final, meeting of two living legends whose unremitting awesomeness has helped define one another, to the benefit of us all.

And if Brady and Manning give us a classic game that evokes memories of that Montana/Elway finale 18 years ago? Well, from our lips to the football gods' ears.

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