How to Use Sports Betting Data to Gain an Edge in Fantasy Football
Jayne Kamin-Oncea- USA TODAY Sports. Pictured: Jimmy Garoppolo.
- Preseason player props/futures and team win totals can be compared to average draft position (ADP) to find over/undervalued players.
- In-season point spreads, over/unders and public betting percentages can inform start/sit decisions.
- Sports betting data is useful because it reflects skin-in-the-game opinions more so than ADP.
Now that sports betting is legal, it’s a good time to review the various ways to use sports betting data to gain an edge in fantasy football.
Before the Draft
League MVP Props
A quarterback almost always wins the Most Valuable Player award (only once since 2007 has a quarterback not won), and the past eight MVP quarterbacks all finished as top-four fantasy players at the position. As a result, you can use the implied probability of a quarterback’s MVP odds as a proxy for his chances to finish as a top-four fantasy quarterback and then compare that to ADP to find over/undervalued players.
For example, five quarterbacks as of writing have +1800 (5.3%) odds of winning the MVP — Cam Newton, Kirk Cousins, Matt Ryan, Philip Rivers, and Dak Prescott — but despite their identical odds they’re going as high as QB6 (Cousins) and low as QB17 (Prescott) in Fantasy Football Calculator’s point-per-reception (PPR) ADP.
Rookie of the Year Props
Show me the NFL Rookie of the Year, and I’ll show you a top fantasy performer:
- The last three quarterbacks to win Rookie of the Year — Prescott (2016), Robert Griffin III (2012), and Newton (2011) — all finished as top-six fantasy quarterbacks.
- The last three running backs to win the award — Alvin Kamara (2017), Todd Gurley (2015), and Eddie Lacy (2013) — all finished as top-seven running backs in standard scoring and top-nine backs in PPR.
- The last three wide receivers to win — Odell Beckham (2014), Percy Harvin (2009), and Anquan Boldin (2003) — all finished in the top 25 at the position in both scoring formats, with 2-of-3 in the top five (Beckham, Boldin).
As is the case with MVP odds, you can compare Rookie of the Year odds with ADP to find value. For example, one sportsbook has +1000 (9.1%) Rookie of the Year odds for Patriots running back Sony Michel, +1400 (6.7%) for Seattle’s Rashaad Penny, and +1800 (5.3%) for Washington’s Derrius Guice, but they’re being drafted in the reverse order at Fantasy Football Calculator.
It’s useful to compare Rookie of the Year odds with ADP in deeper leagues, especially in the late rounds of best-ball drafts. Consider that Cleveland’s Baker Mayfield has +400 (20%) odds to win Rookie of the Year (and thus finish as a probable fantasy QB6 or better), but his ADP in DRAFT best-ball leagues is QB30. For a player being drafted outside of the top 200 (if at all), 20% odds to finish in the top six sounds pretty good.
Win Totals (or Weeks 1-16 Point Spreads)
Players on winning teams are more likely to post high fantasy totals. Of the 100 highest-scoring fantasy games in 2017, winning teams accounted for 79% in standard leagues and 76% in PPR leagues (per Pro Football Reference).
Looking at win totals or Weeks 1-16 point spreads can give you an approximation of how many games a team will win, which you can compare to ADP to find teams that may be over/underrepresented.
For example, the San Francisco 49ers have a win total of 8.5 (with a slight lean on the over) as they enter the first full season of the Jimmy Garoppolo era, but the Niners have only one player (Jerick McKinnon) in the top 70 of Fantasy Football Calculator’s ADP (PPR scoring). On the other hand, the Cleveland Browns have a league-low win total of 4.5 (with a -190 lean to the over, so more like 5.0-5.5), but they have three players (Josh Gordon, Jarvis Landry, Carlos Hyde) being drafted in the top 55.
Other Player Futures (Statistical Leader Props, Etc.)
As they do with the MVP and Rookie of the Year awards, the books post props on players’ odds to lead the league in various statistical categories. With futures (as with weekly player props, which I’ll discuss in a bit), I like to pay the most attention to touchdowns, which are difficult to predict.
Sometimes books provide over/unders for a player’s season total in a particular stat category, which you can compare to your projections or those of popular sites. Over/unders in different categories can sometimes be combined to arrive at an approximate seasonal fantasy projection.
Quarterback Battle Props
One sportsbook released odds on who will end up making more starts in rookie vs. veteran quarterback battles, and these props can be useful in gauging the job security of veterans and upside of rookies, especially in best-ball formats.
For example, among first-round rookie quarterbacks, Sam Darnold of the Jets has the best odds (-175) of starting more games than his team’s veteran signal caller, Josh McCown, while the Ravens’ Lamar Jackson has the longest odds (+500) against Joe Flacco.
During the Season
Favorite vs. Underdog
Winning teams produce more fantasy points, and favorites tend to win more often (67.2% of the time since 2005, according to Bet Labs), so it should be no surprise that players on favorites have scored more fantasy points per game than players on underdogs at every single position since 2014, per our NFL Trends tool.
Point Spread, Over/Under, Implied Team Total
You can use the Trends tool to see how each of these factors impact fantasy scoring at each position, but, generally, the more favorable the point spread, over/under, or implied team total is for the team of a given player, the more fantasy points per game that player is expected to score.
The point spread is also useful for predicting game script, with larger spreads indicating a higher likelihood of positive game script for the favorite (and, thus, a higher likelihood for increased rushing attempts) and vice versa.
Public Betting Percentages
Public betting percentages tend to be more useful in daily fantasy sports, where they provide insight into player ownership, but they can still help with tough start/sit decisions in seasonal leagues. If you’re choosing between players whose teams have similar betting odds, looking at the public betting percentages, particularly the money percentages, can provide insight.
For example, if you’re choosing between two players in games with similar totals, all else being equal you’ll probably prefer the player in the game with a higher percentage of the money on the over. A game with an over/under of 45 points and 75% of the money on the over may have more fantasy upside than one with an identical total but only 25% of the money on the over.
This follows from public betting percentages, which influence the line. You can use the Trends tool to delve into the specifics, but generally a line that moves toward a team or the over will benefit most players involved.
When it comes to reverse line movement (when the line moves against the team getting the majority of public tickets), quarterbacks tend to benefit most.
Weekly Player Props
Sports books don’t always post weekly props for every fantasy-relevant skill-position player, but they can provide some evaluative insight. Touchdowns create the biggest point swings in fantasy, so I like to pay special attention to touchdown props, which can be used to gain a sense of a player’s odds of scoring a touchdown in a given week. (The FantasyLabs NFL Player Props tool compiles a list of all player props posted each week at various sports books, and it also provides Bet Quality Ratings if you’re looking to bet the props.)
MVP props, Rookie of the Year props, and the like can be used during the season to gauge a player’s trade value and find buy-low or sell-high opportunities.
For example, let’s say Michel, who leads all non-Saquon Barkley running backs in Rookie of the Year odds (+1000), gets off to a slow start in the first few weeks of the season. If his odds remain largely unchanged, that could indicate a potential buy-low opportunity via trade.
A Word of Caution
Sports betting data can be useful in fantasy football, but it should by no means be treated as gospel. It’s one of many tools in the toolbox, a way to gain an alternate perspective and the wisdom of the crowd, a way to add in a few box-checking tiebreakers when player projections separated by mere points or tenths of a point are too fragile and rankings too hierarchical.
Especially with props and futures, sites can have drastically different lines due to either their own models or the action they’re getting. As sharp and efficient as the betting market is, sometimes it lags the fantasy market. For instance, Kareem Hunt‘s 2017 ADP shot up much faster than his Rookie of the Year odds after Spencer Ware went down in the preseason.
Ultimately, I think the reason sports betting data is useful is because it takes the pulse of those who have skin in the game, as opposed to ADP data, which is oftentimes derived from either mock drafts or free leagues.
Just remember: While the wisdom of the crowd is often accurate, the ultimate goal is to be wiser than the crowd.