Will you be ready when ‘prop-ortunity’ knocks? Season-long NFL quarterback props are released each summer, and the additional 17th game and passing defense matchups has a different application for this passing yards props than with touchdown props.
It’s just yards, baby. How can bettors find an edge?
I’ve developed a yardage-handicapping tool to uncover potential opportunity zones, regardless of how many times quarterbacks reach the end zone.
It has thus far determined that Seattle Seahawks quarterback Russell Wilson has the league’s most difficult path and that the New England Patriots, Miami Dolphins and New Orleans Saints, regardless of their quarterback concerns, face the most porous pass defense schedules.
Paired with past quarterback yardages, which have a high year-to-year correlation among quarterback stats (explained below), we approach a more reliable 2021 projection.
Let’s go through how these conclusions were reached.
Every formula has a disclaimer. This one is that no totals, offense or defense, will play out exactly to the yardage totals from last season. 2020 was also played with no fans. Even the most advanced statistical modelers will struggle assigning a value to that. Bad luck with weather could also play a roll, as well as team injuries.
We do know NFL rules have led to increased passing yardages in recent years and that year-to-year correlation for quarterback passing yardage has been among the strongest in QB stats.
Overall, this is a starting point for projecting 2021 passing yardage totals.
Projecting Quarterback Props Step 1: Defense Tiers
First, using data from 2020 pass-defense yardage totals, the NFL’s 32 teams were ranked in six tiers. Every five teams constituted a tier and the bottom rung had seven of them.
Tier 1: 193-214 passing yards per game allowed
- Los Angeles Rams
- Pittsburgh Steelers
- Washington Football Team
- San Francisco 49ers
- New Orleans Saints
Tier 2: 215-226 passing yards per game allowed
- Baltimore Ravens
- Green Bay Packers
- New England Patriots
- Los Angeles Chargers
- Arizona Cardinals
Tier 3: 227-238 passing yards per game allowed
- Dallas Cowboys
- Kansas City Chiefs
- Chicago Bears
- Philadelphia Eagles
- Denver Broncos
Tier 4: 239-245 passing yards per game allowed
- New York Giants
- Carolina Panthers
- Buffalo Bills
- Cincinnati Bengals
- Indianapolis Colts
Tier 5: 249-263 passing yards per game allowed
- Tamp Bay Buccaneers
- Miami Dolphins
- Houston Texans
- Minnesota Vikings
- Las Vegas Raiders
Tier 6: 264-293 passing yards per game allowed
- Jacksonville Jaguars
- Cleveland Browns
- Tennessee Titans
- New York Jets
- Seattle Seahawks
- Detroit Lions
- Atlanta Falcons
Projecting Quarterback Props Step 2: Assign Scheduling Point Values
Matchups figure prominently in determining which teams have a favorable situation. Play a Tier 1 team, and we’ll assign one point to the total. A bottom-tier rival is six points. Lowest total for the season represents the most difficult schedule, and the the highest total means the easiest.
Top-Five Toughest Pass Defense Schedules
Seattle: 49 points
Cleveland: 52 points
New York Giants: 52 points
Las Vegas: 52 points
Dallas: 54 points
Top-Five Easiest Pass Defense Schedules
New England 78
New Orleans 72
The Patriots play the Tier 6 Jets, Tier 5 Dolphins and Tier 4 Bills twice each. That’s 30 points in just those six games. The other four teams here are run-heavy offenses and will likely sport new quarterbacks. This deviation could skewer the formula. Beware of that.
Why The Tiers Matter
We’re not talking touchdown props that have historically had high variance from year to year. No one-yard doinks. No tackle eligible plays. According to 4For4’s TJ Hernandez, quarterback passing yards per game has a year-to-year correlation of 0.66, almost triple that of touchdown rate, which has a year-to-year correlation of 0.23.
Combine that with a schedule full of the strongest or weakest pass defenses from a year ago, and we get closer to a data-driven projection. Since 2016, 75% of the top-five passing yardage defenses still finished in the top half of passing yards allowed the following season. Half finished at least in the top 10. On the other end of the spectrum, 75% of the bottom-five passing yardage defenses since 2016 again finished bottom half of the NFL in that category the following season.
There is a big gap, 100 yards yielded each week, between the Tier 1 Rams at 193 and the Tier 6 Falcons at 293. Thus, a team heavily weighted against opponents in Tier 1 and Tier 6 has potential volatility in the prop. A 50–100-yard difference, multiplied over several weeks, could heavily affect a season-long prop bet.
Projecting Quarterback Props Step 3: Add QB Passing Yards Average
Add a quarterback’s game average with the average yards allowed by his combined opponents to form a projected season-long prop.
Sportsbook quarterback props that come close to this total offer no edge. Yardage totals that vary greatly provide potential opportunity.
Test Case: Russell Wilson
Let’s use the formula on the Seahawks long-time quarterback. He averaged 263 yards per game last season. The opponents he faces this year gave up 229 yards per game. That number comes from going through the entire schedule, adding the total yardage yielded by all 17 opponents and dividing the total by 17.
Add 263 and 229 to get 492. Divide by two to get 246 yards per game. That’s the average of Wilson’s offense and his opposing defenses.
Take 246 times 17 (the new NFL season length) to get his 2021 projection of 4,182 yards.
That’s a per game projection significantly lower than Wilson’s past two seasons with 257 yards per game in 2019 and 263 yards per game in 2020. However, this 2021 projection comes pretty close to the well-respected stat projections of ESPN’s Mike Clay, who was even more conservative for Wilson in 2021. Clay projects 4043 yards for Russ, a difference of less than nine yards per game. Our number is also within seven total yards of CBS Fantasy’s Wilson projection of 4,175.
Wilson had 4,212 yards last year in a 16-game campaign. Give him that 263 average for a 17th game last season and he would have hit 4,475 yards. This formula thus projects a dropoff of nearly 300 passing yards for Wilson.
Will sportsbooks reach the same verdict? Wilson’s bettors may want to compare 4,182 yards to the actual prop when it opens. The biggest yard differences, either on the over or under provide the best chances to bet into strength.
Why Might Wilson’s 2021 Yardage Go Down?
Look at these tier 1 and tier 2 opponents. He’s got the hardest matchups in the NFL.
- Week 4: 49ers
- Week 5: Rams
- Week 6: Steelers
- Week 7: Saints
That’s four Tier 1s in a row. There’s a pause for Week 8 with the Jaguars, a Tier 6, but in Week 9, it’s the Packers, a Tier 2. In Week 10, it’s the Cardinals, another Tier 2. Week 11 is Washington, yet another Tier 1. Week 12 is the Niners again. In a nine-week period, half the season, he faces six Tier 1s and a Tier 2.
Test Case: Justin Herbert
Let’s track Justin Herbert of the Chargers, the league’s top rookie last year.
His 4,336-yard total averages out to 289 per game, because he did not start the first game of the year. Add two more 289s to his 15-game total last year and his 2021 total would have been 4,914 yards.
Where does he stand in this formula? Give him 289 yards per game. The defenses he’ll face allowed 236 last year. Add the two to get 525 yards and divide by two to reach 262.5 as the average number. Multiply by 17 and his 2021 projection is 4,462.
Our projection is within 28 yards of Mike Clay’s projection of 4,434. CBS Fantasy is more bullish on Herbert’s 2021 projection, calling for 5,012 yards, likely weighing his maturation and 2020 per game average more
Our projection and Clay’s projection is much lower than his 2020 per game rate, because the defenses he faces are better, but how will the books list it?
Anything near our 4,462 would present a reasonable over bet on the expectation that he’s rising. But if a couple hundred yards of that is already cooked into the line, it’s a tough call.
This is just one basic way to try and project forward for the upcoming NFL season using quarterback stats with higher year-to-year correlation.
Strength of schedule overall is volatile year-to-year, but passing yards for quarterbacks and the best and worst passing yardage allowed defenses are more stable.
Comparing this exercise’s projections with sportsbook quarterback props could expose some blind spots for the new 17-game season.