The two best quarterbacks of 2013 square off Sunday when Indianapolis hosts Denver. While all attention will be on Peyton Manning's homecoming, don't lose focus on the Colts' new franchise QB and his transcendent improvisational skills

Because of his athleticism, Andrew Luck is able to keep plays alive in the face of rushing defenders and find enough room to then use his superior arm strength to finish the job. (Michael Hickey/Getty Images)

You’ll probably encounter more than a few articles about Peyton Manning returning to Indianapolis this week. It’s a great story, especially given that the 37-year-old has been the NFL’s best quarterback in 2013. But this column is about the guy Manning is facing—the guy who replaced him—and why he is the NFL’s second best quarterback in 2013.

Back in July, the Colts 2013 preview here on The MMQB said of Luck:

Here’s what makes Luck special: his toughness and awareness in the pocket; his understanding of the synchronized timing between route combinations, protections and dropbacks; his sense for identifying defensive looks before the snap; his sense for confirming or rethinking defensive looks after the snap; his command for the subtle body-language mechanics that quarterbacks use to manipulate defenders (think Tom Brady’s shoulder flinches or Drew Brees’ hesitation fakes); an arm that is not super strong but powerful enough to always get the ball there on time; his accuracy, both off a plant-and-drive or on the move; his ability to extend plays in and out of the pocket; and, finally, killer good looks (okay, just kidding).

These are skills the 24-year-old has shown, but not yet mastered.

Six games into his sophomore season, Luck still has not “mastered” anything, but he’s startlingly close in a lot of areas. He doesn’t begin to have the stats that his Week 7 counterpart has (Luck ranks just 20th in yards and 17th in touchdowns). But, like Manning, he is overwhelmingly the main reason his club sits atop its division.

In this day of finesse spread passing games and illusory read-option rushing attacks, Indianapolis’s offense is something of a relic. It features a power running game and a deep-drop passing game that leans heavily on play-action. With today’s increasingly sophisticated defensive schemes and athletes, few offenses can still play this way.

The Colts can because of Luck, which is remarkable given that the pieces around him are fairly ho-hum. Aside from burgeoning star Anthony Castonzo at left tackle, the offensive line lacks athleticism. Through four games, running back Trent Richardson has looked as mundane in blue and white as he did in brown and orange. Richardson does not have the initial quickness or lateral agility to consistently create his own space. Indy’s receiving corps is good but not great. The venerable Reggie Wayne can still get open, and second-year pros T.Y. Hilton and Coby Fleener are ascending. But neither has fully arrived. This, and iffy depth, keeps this group from being in the upper echelons.

Fortunately, Luck is capable of spinning mediocrity into greatness. There are two significant factors behind his alchemy. First, Luck has a great feel for the intricacies of new coordinator Pep Hamilton’s system, which has helped him improve in the presnap phase. (More on this in a moment.) Secondly, Luck is unbelievable in the way he extends plays.

That’s what all great NFL quarterbacks do—extend plays. There are two types of play-extending quarterbacks. One: the cerebral, fundamentally sharp quarterbacks who are poised in the pocket and able to consistently work deep into progressions (think Manning, Brady, Brees). The other: the creative, more dynamic quarterbacks who have exceptional physical gifts that enable them to make something out of nothing (think Roethlisberger, Romo, Kaepernick). Luck is the rare blend of both types. In fact, he might be the purest blend ever seen.

Obviously, these “types” are not black and white. Great pocket quarterbacks can also make athletic, improvised plays. Great improvisational quarterbacks, though inherently less consistent, can also play smart and sound from the pocket. And we’ve seen immensely talented quarterbacks before who can consistently be either type (Aaron Rodgers comes to mind). But Luck is not just “either” type; he’s “both” types. This is to say, he’s not just brilliant in the pocket on one down and brilliant in sandlot on the next down; he’s brilliant in both ways simultaneously.

Luck has an extraordinary knack for maintaining the structure of a play when improvising. He does not create magic when things break down; he creates magic by not letting things break down. Here are some examples:

Luck makes these sorts of plays every week. Thrilling as they are, they’re not what he and the Colts prefer. Truly great offenses do not just react well to the game’s various circumstances; they control the circumstances. This is done through presnap diagnostics and adjustments. Obviously, Manning is the king of this. Luck is not yet near that level, but he’s rapidly climbing. We saw a great example of this a few weeks ago.

Sunday night will be a fantastic showcase not just for the past and future of elite quarterbacking, but for the present. The two best quarterbacks of 2013 will be on the field.

Continue to Page 2 for my Cardinals-Seahawks Thursday night preview.

THURSDAY NIGHT GAME

Richard Sherman (center) and the Seahawks defense were able to keep Larry Fitzgerald in check last season, allowing only five catches for 65 yards and no touchdowns in two games. (Christian Pedersen/Getty Images)

Cardinals offense vs. Seahawks defense

Richard Sherman would probably love the challenge of shadowing Larry Fitzgerald on a national stage. But since Brandon Browner returned a few weeks ago, the Seahawks mostly have kept their corners in their usual spots: Sherman along the left boundary, Browner the right boundary and Walter Thurmond inside.

Seattle’s Week 5 opponent, Indianapolis, often overloaded wide receivers to the same side of the field in order to either create mismatches against ancillary pass defenders or force a cornerback to play somewhere he’s not accustomed to playing. Expect Arizona to use the same overload tactics. Bruce Arians already has a lot of these concepts built into his passing attack.

If the Cards go with more trips formations, it would make sense for Sherman to follow Fitzgerald (especially when you consider that Browner has struggled with man concepts the past two weeks and would not thrive in this matchup). It might not matter who guards Fitzgerald anyway; it’s hard to envision Arizona’s O-line keeping Seattle’s increasingly fearsome pass-rush at bay.

Seahawks offense vs. Cardinals defense

Richard Sherman has been the best cornerback in football this season; Patrick Peterson is not far behind him. Whoever Peterson shadows should effectively be removed from this game, as none of Seattle’s wideouts are particularly dynamic. That’s true about the entire passing attack, actually. Russell Wilson has not been awful, but he has not been as sharp as he was at the end of last season.

The Seahawks have overcome aerial mediocrity so far because they’ve committed to a ground-oriented approach. According to Football Outsiders, the Seahawks have run the ball on 53.9 percent of their first-down snaps, second only to the Bills. And they’ve utilized play-action on 35.4 percent of their passes, most in the NFL.