When the Broncos traveled to Indianapolis last October, the Colts sacked Peyton Manning four times. That was quite a feat, given Manning may be the hardest quarterback to sack in NFL history.
That may seem like a bold claim, but Manning's career record has the evidence to support it. He has attempted over 8,400 times and been sacked 270 times, just 3.1 percent of the time. That is the best rate in NFL history, narrowly edging out Dan Marino.
Manning has never had as great a season as Marino's 1988, when he was sacked just six times despite attempting 606 passes. One thing Manning does have on his side, though, is remarkable consistency at avoiding sacks.
Raw rate is not the best measure of a quarterback's ability to avoid sacks. Quarterbacks are more likely to be sacked in certain situations, particularly third-and-long, and when facing opponents that get more sacks. Football Outsiders developed their Adjusted Sack Rate statistic to account for these fluctuations in base sack rate.
It came as no surprise the Broncos had the league's best Adjusted Sack Rate last year. 2013 was the eighth time in Manning's career his team allowed the fewest sacks in the league by ASR. Five more times his team finished second. Only twice in his fifteen seasons as a starting quarterback has his team ranked outside the top two in ASR, when the Colts ranked fifth in 2007 and seventh in 2001.
Those consistent results have occurred behind some pretty good offensive lines and some pretty bad ones. It seemed like Manning might be joining a bad Broncos line. In 2011, the Broncos posted the fourth-worst Adjusted Sack Rate in the league. We know, though, that sack rates tend to be consistent for quarterbacks when they change teams.
Further, quarterbacks on the same team sometimes have very different sack rates. That 2011 Broncos squad gave us an excellent example of this. Kyle Orton started the first five games and Tim Tebow played the rest of the season. With Orton at quarterback, Denver's Adjusted Sack Rate was a fine 5.3 percent. With Tebow in the lineup, the Broncos' Adjusted Sack Rate was an abysmal 11.2 percent. Was Manning joining a good pass-blocking unit, as the Orton numbers suggest, or a bad one, as the Tebow numbers suggest?
Different sack rates for teammates playing behind the same offensive line help explain how a quarterback so obviously immobile and unathletic (by NFL player standards) as Manning can consistently be sacked so little. A quarterback's sack rate seems to be the result of how he executes the plays that are called for him rather than a measure of the effectiveness of the blocking or how mobile he is.
Being a mobile quarterback actually may hurt a quarterback's sack rate rather than help it. We can see this with lesser players like Terrelle Pryor, who posted a sack rate treble the less athletic Matt McGloin's on the 2013 Raiders, but also with fine quarterbacks like Aaron Rodgers or Ben Roethlisberger. Rodgers and Roethlisberger will try to, and sometimes succeed in, making a play Manning would not attempt.
Looking across the other sideline on Sunday night, that contrast between Manning on one hand and Rodgers and Roethlisberger on the other is instructive. Andrew Luck has been hit more the past two years than any other quarterback in the league. The Colts rightly want to protect him from that kind of damage, but not all of those hits were due to a porous Indianapolis offensive line. Like the Packers and Steelers, the Colts may eventually have to come to terms with the fact they have a fine quarterback who takes sacks at an average or above-average rate instead of a maestro of sack-avoidance like they used to have in Manning.
What It Means for Sunday Night
The Colts last year were the first team to sack Manning four times since the Atlanta Falcons did it in 2007. As hard as Peyton is to sack, the Colts would be unlikely to get to him four times even if everything was the same as it was last year.
Things are most emphatically not the same. First, the game is in Denver instead of Indianapolis and will be quiet instead of loud when the Broncos are on offense. Second, Robert Mathis was one of the best pass rushers in the league last year, and had two of those sacks of Manning. He will miss this game due to a suspension. The Colts have no other proven pass rusher on the roster. Mathis beat Chris Clark for his sacks. Clark was only playing left tackle because the Broncos lost Ryan Clady to a knee injury early in the season. Clady was one of the league's best left tackles before his injury, and he is back at his customary spot.
The combination of change of venue, less ferocious Indianapolis pass rush, and better protection could make this another game, like the six he had last year, where Manning does not get sacked even a single time.