Fantasy Football: Examining the Impact of Projected Win Totals on Game Script
Game script is extremely important when deciding who to play each week in fantasy football.
When a team wins a lot of games, they typically see more positive game scripts, meaning they are playing with a lead more often. When this happens, they may shift how their offense is run.
Running backs expected to trail will struggle to see big-time rushing volume, and wide receivers on big favorites could have their volume capped in a blowout win.
Why not put this to the test and see how that might impact the 2020 season?
I decided to take a look and see how teams' game scripts changed year to year with a focus on teams whose projected win total line (based on betting over/unders) was 2.5 wins greater or fewer than their actual previous season win total.
The thought here is that teams projected to win 2.5 more games in the upcoming season compared to the previous year should see fewer negative game scripts. The opposite can be said for teams that are projected to lose 2.5 more games than they did the previous year.
I defined a "trailing" game script as when a team was losing by 10 or more points. "Leading" was when a team was winning by 10-plus points. Neutral game script is when a game is within seven points.
Teams Expected to Lose More
Below is a table for teams from 2017 to 2019 that had a projected win total that was at least 2.5 games fewer than their previous year's actual win total.
|Leading Play %
Those teams, on average, saw their play percentage while leading by 10-plus points drop by 4.1 percentage points the following year.
On average, these teams had 54 fewer plays when leading. Further, 8 of these 13 teams saw a decrease in the number of plays run when leading. Of the five that didn't, the largest change in number of plays was 39.
Essentially, this means that no team anticipated to win significantly fewer games bucked the expected trend and saw a ton of extra plays with super positive game script.
Of the teams that saw a decrease in positive script play percentage, four of them ran 100-plus fewer plays with positive script. In fact, the average decrease of those teams was 99 fewer plays per season in a leading game script.
Again, what this means is that, when we see a team win significantly more games one year and then be projected to win 2.5 or fewer games the following year, a lot of them see a huge decrease in plays with a 10-point lead.
Vegas win totals may not always lead to identifying large decreases in leading game script, but they do seem to be useful in finding teams that already were at or near their ceiling in terms of being up by more than one score in games for the season.
Teams Expected to Win More
Below is a list for teams from 2017 to 2019 that had a projected win total that was 2.5 games more than their previous year's total.
|Trailing Play %
On average the above teams saw a decrease in trailing game script of 6.0 percentage points, resulting in an average of 51.7 fewer plays when trailing across the sample.
Only 4 of the 18 teams listed above did not see a decrease in trailing game scripts -- that means the projected win totals accurately predicted 77.8% of the teams to see more neutral or leading game scripts.
The 2019 Jacksonville Jaguars were the only team to see at least 100 more plays in trailing game scripts. Vegas was likely betting on Nick Foles to be a significant improvement over previous Jags quarterback Blake Bortles.
If we look at only the teams that did end up being behind less often the following year, those teams averaged a decrease of 79 trailing plays for the season.
This, then, shows the inverse of the prior section. Teams expected to be better than they were the prior year spend less time getting blown out. That's a bit obvious, but it's never a safe assumption to make without seeing what the data actually shows.
Which teams, then, fit the bill for 2020?
Using current win total projections for the upcoming season, we can examine which teams have the highest likelihood of seeing different game scripts than they did the previous season.
Currently, 11 teams are projected to win or lose 2.5 or more games than they did in 2019 based on win totals from FanDuel Sportsbook. These are the teams we should focus on for the upcoming season when looking for large shifts in game script.
The next step will be to identify how these specific offenses changed when in these different game scripts.
The obvious difference is that teams run the ball more often when they have the lead, especially late in the game. The Baltimore Ravens, San Francisco 49ers, New Orleans Saints, New England Patriots, Green Bay Packers, and Houston Texans should see a significant decrease in plays run with a huge lead. As such, that could lead to elevated passing rates from what they had last season.
The not-so-obvious changes to dig into come at the team level. Did a particular team run the ball with a different player because they had a big lead as opposed to being in a close game? Maybe a team targets a certain wide receiver more often when they are trailing big versus when they are down only three points. Which teams ran the ball a lot when losing or in a neutral script regardless?
My follow-up article will focus on these teams that are projected to win more often in 2020 than they did in 2019 and will apply what we learned here to anticipate how game script will impact some of the NFL's most intriguing fantasy football offenses.