There’s been a lot of talk this week about the gutless sieve that passes for Indy’s run defense.

It became the center of attention as the Colts outlasted Denver, 34-31, on Sunday despite surrendering a horrific 227 yards on the ground, and an average of 6.3 yards per attempt.

As most football fans know by now, Indy has the worst rush defense in football. They allow 167.9 yards per game on the ground.

But here's an even more telling stat: They allow 5.4 yards per rush attempt. That’s a full half-yard worse than the 31st team on the list, the Titans, and double the 2.7 yards per attempt yielded by the league’s No. 1 run defense in Baltimore.

But hang on to your nuggets, friends of the Cold, Hard Football Facts. There’s more to it that you just don’t know … yet.

The good folks at ESPN were kind enough recently to send a few copies of The ESPN Pro Football Encyclopedia to the CHFF cardboard-box world headquarters, condemning us in the process to at least another year without sunlight or the scent of a woman.

The encyclopedia includes statistical data for every team in NFL history — including the number of yards each team allowed per rush attempt.

We wanted to find the last time a defense surrendered 5.4 yards per rush attempt, so we started flipping through the encyclopedia. And we flipped through page … after page … after page … after page.

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We didn’t stop until the calendar read 1961. And there, in the black and white of irrefutable Cold, Hard Football Facts, was the last run defense worse than that of the 2006 Colts: It belonged to the 1961 Vikings, an expansion team from nearly a half-century ago, which surrendered 5.41 YPA.

The Colts' run defense right now finds itself among some ignominious company. In fact, there are just 13 teams in NFL history that have surrendered more than 5.0 yards per rush attempt over the course of a season. Nearly half were expansion teams. Just five teams in history have had run defenses worse than Indy's. Four of those five were expansion teams.

It's not pretty, folks.

NFL Worst run defenses in NFL history Year Team Record Att. Yards YPA 1934 Cincinnati Reds 0-8 255 1,631 6.40 1950 N.Y. Yanks 7-5 434 2,445 5.63 1950 Colts 1-11 514 2,857 5.56 1959 Redskins 3-9 404 2,214 5.48 1961 Vikings 3-11 493 2,667 5.41 2006 Colts 7-0 219 1,175 5.37 1958 49ers 6-6 380 2,038 5.36 1955 Bears 8-4 398 2,100 5.28 1951 Bears 7-5 372 1,958 5.26 1953 Colts 3-9 445 2,315 5.20 1976 Chiefs 5-9 555 2,861 5.15 1956 Packers 4-8 512 2,619 5.12 1973 Patriots 5-9 560 2,850 5.09 1960 Cowboys 0-11-1 447 2,242 5.02

A list of the worst run defenses in NFL history is at left, followed by the stories behind the five worst.

The first thing that jumps out is that it’s a miracle the Colts are undefeated at this point despite fielding a rush defense that stands among the very worst in NFL history. As you see, almost all of the other teams on the list sucked. With the exception of the Colts, they posted a combined 52-105-1 (.332) record.

But the futility of Indy's run defense is even more shocking when you consider the historically inept company the Colts are keeping.

The 1934 Reds (6.40 YPA) folded after the season and after a 3-14-1 record in their two short years of existence. The 1950 Yanks (5.63 YPA) joined the NFL that year from the old All-America Football Conference, which existed from 1946-49. They folded at the end of the 1951 season. The 1950 Colts (5.56 YPA) were also AAFC refugees. They folded at the end of the season before rejoining the NFL in 1953 (and again finding their way onto our list). The 1961 Vikings (5.41 YPA) were an expansion team that year.

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That leaves the 1959 Redskins (5.48) as the only legitimate team in NFL history that has fielded a run defense worse than the one that currently resides in Indianapolis.

What's it mean for the Colts? Well, right now, the only statistic that matters is their 7-0 record. But it's hard to imagine a more unbalanced team: one that's historically prolific in the passing game but historically inept in its run defense.

And as history has proven, balance is almost always one of the essential elements of a championship team.

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