Drew Lock completed 56.9% of his passes in college and had a TD:INT ratio of 2.54:1.00 (99 TD and 39 INT). Keep that in mind as you read this study.
So I wrote this in 2017 when we were all wondering if Trevor Siemian could become an average NFL QB (spoiler: he couldn’t) based upon his terrible stats from college. That got me thinking about whether or not college QB stats, particularly from pass-wacky offenses, had any real bearing on NFL performance. So I dug into the numbers. This will update that study with QB stats from the 2017, 2018 and 2019 seasons.
The original study included 52 starting QBs, but did not look at players who played FCS or D2 in college, so I will continue to use that method. The original study also focused on two stats: completion percentage and TD:INT ratio. So will the updated study. Only guys who were starting QBs for multiple seasons in the NFL are included (starting 8 or more games at least twice) over the last 15 NFL seasons. The game has changed quite a bit since 2005.
Change in Completion Percentage
|Rank||QB||NFL COMP%||College/Univ||College COMP%||Change in COMP%|
|1||Josh McCown||60.2%||Sam Houston St.||51.2%||9.0%|
|4||Matt Ryan||65.4%||Boston Col.||59.9%||5.5%|
|6||Matt Hasselbeck||60.5%||Boston Col.||55.6%||4.9%|
|8||David Garrard||61.6%||East Carolina||57.0%||4.6%|
|9||Tyrod Taylor||61.6%||Virginia Tech||57.2%||4.4%|
|11||Derek Anderson||54.3%||Oregon St.||50.7%||3.6%|
|14||Brian Hoyer||59.1%||Michigan St.||55.8%||3.3%|
|15||Dak Prescott||65.8%||Miss. St.||62.8%||3.0%|
|16||Kirk Cousins||66.9%||Michigan St.||64.1%||2.8%|
|18||Patrick Mahomes||65.9%||Texas Tech||63.5%||2.4%|
|22||Philip Rivers||64.7%||North Carolina St.||63.6%||1.1%|
|23||Ryan Tannehill||63.5%||Texas A&M||62.5%||1.0%|
|27||Marc Bulger||62.1%||West Virginia||61.6%||0.5%|
|28||Jacoby Brissett||59.9%||North Carolina St.||59.5%||0.4%|
|31||Michael Vick||56.2%||Virginia Tech||56.0%||0.2%|
|37||Ben Roethlisberger||64.3%||Miami (OH)||65.5%||-1.2%|
|38||Josh Freeman||57.6%||Kansas St.||59.1%||-1.5%|
|39||Christian Ponder||59.8%||Florida St.||61.8%||-2.0%|
|40||Derek Carr||64.0%||Fresno St.||66.7%||-2.7%|
|42||David Carr||59.7%||Fresno St.||62.7%||-3.0%|
|48||Mitch Trubisky||63.4%||North Carolina||67.5%||-4.1%|
|51||Jameis Winston||61.3%||Florida St.||66.0%||-4.7%|
|58||Blake Bortles||59.3%||Central Florida||65.7%||-6.4%|
|63||Geno Smith||57.9%||West Virginia||67.4%||-9.5%|
Of the 64 quarterbacks in the study 31 of them improved their completion percentage in the NFL relative to what they did in college. The average change over the whole study was a 0.6% drop in the NFL relative to college numbers. Most of the QBs that significantly improved their completion percentage are not currently starters in the NFL but a few are - Drew Brees, Matt Ryan, Matthew Stafford, Russell Wilson, and Dak Prescott. The standard deviation of the college completion values was 4.8 percent. The average change was -0.7 percent.
On the other end of the spectrum you have about the same number of current NFL starters who have gotten significantly worse in the NFL: Mitch Trubisky, Jameis Winston, Nick Foles, Sam Darnold, Cam Newton, Case Keenum, and Baker Mayfield. I did not realize before writing this that Colt McCoy completed more than 70 percent of his passes in college.
Touchdown to Interception Ratio
While it appears to be relatively “easy” to improve upon college completion percentage once you are starting in the NFL, it is much more difficult to improve upon college passing TD to interception ratio. Only twelve of the QBs in the study were able to do that.
|Rank||QB||NFL TD/INT||College/Univ||College TD/INT||Change in TD/INT|
|3||Patrick Mahomes||4.2||Texas Tech||3.2||1.0|
|4||Matt Ryan||2.2||Boston Col.||1.5||0.7|
|5||Tyrod Taylor||2.7||Virginia Tech||2.2||0.5|
|6||Matt Hasselbeck||1.4||Boston Col.||0.9||0.5|
|8||Josh McCown||1.2||Sam Houston St.||0.8||0.4|
|12||David Garrard||1.6||East Carolina||1.5||0.1|
|14||Kirk Cousins||2.2||Michigan St.||2.2||0.0|
|15||Josh Freeman||1.2||Kansas St.||1.3||-0.1|
|18||Ryan Tannehill||1.8||Texas A&M||2.0||-0.2|
|20||Dak Prescott||2.7||Miss. St.||3.0||-0.3|
|22||Michael Vick||1.5||Virginia Tech||1.9||-0.4|
|23||Marc Bulger||1.3||West Virginia||1.7||-0.4|
|25||Derek Anderson||0.9||Oregon St.||1.4||-0.5|
|27||Christian Ponder||1.1||Florida St.||1.6||-0.5|
|28||Ben Roethlisberger||1.9||Miami (OH)||2.5||-0.6|
|31||Jacoby Brissett||2.4||North Carolina St.||3.1||-0.7|
|34||Brian Hoyer||0.8||Michigan St.||1.5||-0.7|
|35||Philip Rivers||2.0||North Carolina St.||2.8||-0.8|
|38||Jameis Winston||1.4||Florida St.||2.3||-0.9|
|47||Blake Bortles||1.4||Central Florida||2.9||-1.5|
|55||David Carr||0.9||Fresno St.||3.0||-2.1|
|56||Derek Carr||2.3||Fresno St.||4.7||-2.4|
|57||Mitch Trubisky||1.7||North Carolina||4.1||-2.4|
|62||Geno Smith||0.8||West Virginia||4.7||-3.9|
The top four are all still starting QBs in the NFL (and five of the top seven). On the other end of the spectrum you can see that many of these QBs were not able to get anywhere close to the TD:INT ratio that they posted in college. The standard deviation on the college TD:INT ratio was 1.3. So 21 of these QBs have been (were or still are) significantly worse in the NFL than they were in college. This should surprise no one. What should stand out to people is the fact that, of the bottom ten here, eight of them were either the first or the second pick in the draft. Only Geno Smith and Derek Carr were not.
What does this mean for Drew Lock (if anything)?
In his five game audition in 2019, Drew Lock was able to complete 64.1 percent of his passes. That’s a 7.2 percent change for the better relative to his college career. Were he to maintain that, he would be #3 in this completion percentage table. Lock threw seven touchdowns and only 3 interceptions. That ratio of 2.33:1.00 is fairly close to his college performance (2.54:1.00). The average change was -1.0, meaning that most QBs got significantly worse in the NFL relative to college. The standard deviation of the NFL TD:INT ratio was 0.74.
It would not surprise me if both Lock’s completion percentage and his TD:INT ratio stay the same in 2020 relative to 2019. The league average for completion percentage in 2019 was 63.5 percent. Only four teams completed fewer than 60 percent of their passes and the worst team in the NFL, the Bungals, still completed passes at a higher percentage 57.8 percent than Drew Lock did in college. Lock’s improvement in completion percentage is almost to be expected since his college completion percentage was so low. Both Lock and Josh Allen had their draft stock hurt by their “poor” college completion percentage. Their stats are even more glaring when you realize that seven different BCS starting QBs last season completed 70 percent (rounding up) or more of their passes.
|2019||Anthony Gordon||Wash St||SR||13||687||493||71.8||5579||8.1||48||16||3.0||158.4|
|2019||Ty Storey||Western Ky||SR||11||345||241||69.9||2567||7.4||14||7||2.0||141.7|
What is more likely to occur in 2020 for Drew Lock?
This poll is closed
maintain both his completion % and his TD:INT
Improve completion % and maintain TD:INT
maintain completion % and improve TD:INT
get worse in both
get worse in completion % and maintain TD:INT
get worse in TD:INT and maintain completion %