Eras favor Unitas, but defensive complexities give Brees the historical nod

In 1960, the year that Johnny Unitas completed his streak of 47 straight games with a touchdown pass, #19 also led the league in touchdown passes ... with 25. In 2011, the man who led the league on passing touchdowns was Drew Brees, with 46, and Brees had 25 by Week 11. This is one of many reasons you'll hear people say that while Brees' 48-game touchdown streak, which he established against the San Diego Chargers on Sunday night, it is still not on the same level as the mark Unitas set.

Unitas, historians will tell you, set his mark in an era far more about the run than the pass, and that's true. The NFL was still a ground-based league, and as the American Football League was just getting underway and hadn't established its own reputation for wide-open football that would change the game forever, Unitas did something that wasn't even believed to be possible.

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That's a valid point, as is the assertion that in Unitas' day, receivers were mugged constantly by aggressive defenders like Dick "Night Train" Lane and Hardy Brown. Today's NFL, many will tell you, is so set up for the quarterback, it's a near-miracle that someone else didn't set the mark before.

The problem with that theory is that it fails to account for the fact that the defenses Brees faces on a week-to-week basis are so much more complex than what Unitas had to deal with, the difference can barely be explained. Unitas played in an era in which many teams didn't yet run the 4-3 defense, which was established by New York Giants defensive coordinator Tom Landry in the mid-1950s. Before Landry's 4-3 and flex concepts, many teams played straight five-man fronts, aligned and assigned to stop the run.

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That's the counter-argument to the "Unitas did what he did before the NFL became a passing league" argument -- Unitas also did what he did when most defenses didn't even know how to defend the pass in a modern sense. The zone passing defense wasn't really in play in the NFL until the late 1960s, and the pure 3-4 defense, which really started in the AFL, wasn't a universal football conceit until the two leagues merged in 1970.

The 3-4 then grew into the precursor to today's multiple and hybrid fronts when the New York Giants selected linebacker Lawrence Taylor in the 1981 NFL draft and gave rise to the pass-rushing lineman who could move all around the front and confound quarterbacks from different angles and attack points.

From there, the expansion of NFL defenses went to a different dimension. Cincinnati Bengals defensive coordinator Dick LeBeau devised the zone blitz in the early 1980s in part to counter Bill Walsh's West Coast offense, and all of a sudden, quarterbacks couldn't be sure whether linemen were dropping into coverage at the same time defensive backs were blitzing.

Nickel and dime defenses grew in popularity to counter other offensive developments, and coverages became more complex every year. LeBeau, Bill Belichick, and many other defensive geniuses were like mad scientists in laboratories, inventing new ways to torture quarterbacks from a schematic perspective with alarming regularity.

As a result, the sheer amount of things Brees and other modern quarterbacks must decipher at the line of scrimmage puts it past the idea that Brees and his contemporaries are playing chess while guys in Unitas' time were playing checkers -- we're talking more about the difference between the early Henry Ford motor cars and the technology that allowed men to walk on the moon.

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Nobody would or should be foolish enough to assume that Unitas, or Bart Starr, or John Brodie, or many other signal-callers of Unitas' time, would not be able to adjust to the modern game. The odds are that they could.

But that's the point -- they would have to adjust, and the adjustments would be severe. And that's why, as easy as it is to dismiss Brees' ability to pass a record that some thought would never be broken as a byproduct of today's game, to do so is to ignore the fact that the things Brees has to deal with on the field make his accomplishment all the more impressive.

Put it this way -- if Brees faced the earthbound, vanilla defenses Unitas went up against, he'd probably be good for 5-10 touchdown passes per game. That's the way evolution goes, and Drew Brees is that modern quarterback in the best possible sense.

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