Much was made of how unreliable former running back Michael Turner had become in 2012, while Steven Jackson has been widely heralded as a smart signing.
Almost everyone seems to agree that S-Jax is a superior replacement to "The Burner" in the backfield. In fact, I do just that in the last Stataholic post, which compares the production of Turner and Jackson.
But was comparing two running backs, as if they existed alone in a bubble, totally accurate? Both played for different teams, and thus both played behind different offensive lines. And if the advanced numbers on Atlanta's front five are any indication, then Turner did not exactly have great blocking last season.
If we take a look at Football Outsiders' O-line rankings, Atlanta's "Power Success" rating, which measures the "percentage of runs on third or fourth down with two yards or less to go that achieved a first down or touchdown," ranked dead last in the entire league at a 39% success rate.
The Falcons also ranked 27th in the league in the percentage of runs that were stuffed at 23%. And the team's "Adjusted Line Yards" (ALY) of 3.87 per carry was ninth-worst in the NFL.
Compare that to Atlanta's pass protection numbers: the Falcons ranked eighth in the league in adjusted sack rate (5.1%), which gives sacks per pass attempt adjusted for down and distance.
Is that a result of the team's play-calling? It's obvious to anyone that watched the Falcons last season that the offense was passing more, utility Matt Ryan and the plethora of weapons at his disposal, rather than running it up the guy with Turner as one Mike Mularkey so often did (who apparently had a "penchant for specialty plays" while with the Steelers).
Interesting in all of this is that while notably sub-par at running the football between the tackles after relying on that ability for several years under Mularkey, the Falcons excelled at off tackle runs to either side. The Dirty Birds ranked fifth in ALY running left tackle and eighth running right tackle.
So I think when you take that into consideration, the answer to "why did Atlanta's run game decline?" is threefold:
1) Turner's wear and tear, along with his somewhat limited skill set, caused his value to decline at running back. It also tipped teams off that, whenever he came into the game, the Falcons would most likely run or call play-action.
2) The offensive line had aging starters that were not as successful blocking runs in between the tackles where Turner usually thrives. Thus, his production dropped off a cliff.
3) Part of this was also by design. The Falcons were running less partly because they were not as successful, but also because the team was so successful at passing with Ryan. It became clear from the outset that this team would aim to win ball games by getting out to a fast start on offense and allowing the defense to make its living off of minimizing penalties and forcing turnovers.
All of these reasons also reinforce the fact that Steven Jackson was, as previously stated, a great signing that makes Atlanta's offense even more dangerous than it was in 2012. Good luck, Rob Ryan-led Saints defense.