So far this season, teams have converted on 37.2% of all pass plays on third or fourth downs. Looking at success rates on these downs helps to identify which quarterbacks are keeping drives alive for their teams and coming through in the most important situations. For example, Peyton Manning leads the league with an impressive 52.6% rate. How impressive is that?
The table below lists the conversion rates for quarterbacks on passing plays (excluding scrambles) on third and fourth downs; the table is sorted by the far right column, which shows how many third downs over average each quarterback converted. This is calculated by subtracting from the number of actual conversions the number of expected conversions (which is 37.2% multiplied by the number of third down plays):
Peyton Manning has been exceptional on third downs, with Ben Roethlisberger and Matt Ryan not far behind him. On the other side of the coin, Andy Dalton, Joe Flacco, and Cam Newton have struggled with higher expectations in 2012, particularly on third downs.
But not all third downs are created equally. The number of yards needed is obviously strongly correlated with the success rate:
It makes no sense to group all third down conversions together when the amount of yards needed is such a critical element. So here’s what I did. For each quarterback’s third or fourth down passing play, I credited him with the expected number of first downs based on the amount of yards to go. So if a quarterback had a 3rd and 5, I credited him with 0.429 expected first downs. If he threw for a first down, he gets credit for +0.571 first downs above average; if he fails, he gets credited with being 0.429 first downs below average. Add that up for each quarterback in each situation, and you can get a true measure of how each quarterback fared on third downs.
For each quarterback, the table below lists his number of third/fourth down pass plays, number of converted third/fourth downs, his expected first down rate based on the yards to go in each situation, his actual first down conversion rate, and the difference between those two numbers. The final two columns show the number of expected first downs (based on the amount of yards to do in each third/fourth down) and the far right column shows the number of first downs converted over average.
If you sort by the “Exp1D_Rt” column you get a sense of which quarterbacks throw most frequently on third/fourth down in easy situations. Drew Brees ranked 4th in raw third down conversion percentage, but after adjusting for distance, he drops to 8th. Eli Manning takes an even more severe hit, and he ranks just 27th in adjusted third down success. On the other hand, Cam Newton has been placed in the worst third down position, which I noted a couple of weeks ago.
The AFC North holds the #2 quarterback in third/fourth down performance, Ben Roethlisberger, and then three of the worst five quarterbacks in these situations. Andrew Luck has been magnificent on third down, one of the reasons he ranks highly in ESPN’s Total QBR. But for now, Peyton Manning remains the king.