Championship Players 2020: What players won or lost your fantasy football championships
Every year, I love to see which players were the most common on fantasy football champion rosters. It always provides a nice snapshot of what players or positions performed, both across the entire season in order to make the playoffs and during the playoffs to actually win the championship. This year, I decided to do my own analysis.
As per my previous posts, I will be using data from public ESPN leagues. There will always be limitations with this, but taking it in the aggregate can still give us a sense. To that end, I collected the final rosters from over 7000 fantasy teams, along with other stats about their team such as regular-season standing, final standing, points for, and win total. Most of these teams will be full point PPR (as that is the ESPN standard) and their roster will be 1QB, 2RBs, 2WRs, 1TE, 1Flex, 1K, and 1DST. Finally, to control for some outliers I filtered out any player rostered in less than 30% of leagues.
Lets first look at the 10 most common players on championship-winning rosters
This table really shows a nice mix of top picks (Henry, Kamara, Adams), mid-level picks who overperformed (Diggs, Waller) and some waiver wire finds (Wilson, Gaskin, Herbert, Thomas, and Koo). We also see the bias towards running backs as we would expect. Stefon Diggs is clearly the most common player, being on more than a quarter of championship teams, we quickly drop off. As analysts often say, there are many ways different ways to build a winning championship team.
Of course, having a championship team isn't any use if you don't first make the playoffs. So Lets next look at the players on the top 4 seeds entering the playoffs. (Note I am arbitrarily creating the top 4 cutoff, while many leagues have more teams making the playoffs, focusing on the top 4 is a safe bet).
Remember that the playoff roster percentage will be higher because a player only needs to be on one of 4 teams rather than on 1 specific team. Given that though, we can get a sense of the players who really performed all year vs those that busted in the playoffs. Players like Travis Kelce (59% playoff teams but only 16% of championship teams) and Kyler Murray (56% playoff teams but only 10% of championship teams) really performed through the regular season but not in the playoffs. We can also see the flip side where players like Stefon Diggs, Darren Waller, and Logan Thomas were on a lot of championship rosters but did not necessarily give your team the best chance of making the playoffs.
Understanding which players were common is only a first step though. We can actually flip this on its head and ask what are the odds of winning a championship if you have a certain player. To do this we need to use Bayes theorem, which is the underlying theorem to most conditional probability calculations you hear about. For example, the player that gave its owner the best chance of winning their championship was Jeff Wilson jr. at 26%. That would mean that if you have Jeff Wilson Jr. on your team, you had a 26% chance of winning the championship. That number is calculated by taking the odds of the player being on the championship team (number of champions with him / number of leagues) times the probability of any team being the league champion (1/league size) and divide that by the odds of the player being rostered (his roster percentage).
Based on this, here are the 10 players that gave you the best chance of winning a championship.
Again, we see a slightly different picture than before. The real thing that stands out to me here is the lack of 1st round picks. There is Derrick Henry and Alvin Kamara, but that is it. Compare that to players that were only good in the last few weeks of the season (such as Jalen Hurts who didn't start until the fantasy playoffs). Taken together, this really drives home that you should not be starting the players that got you there when you make the playoffs, you start the players that give you the best chance that week. This could be players that were good all year, but it may be waiver wire finds, and winning a championship means being willing to start a guy you picked up off of waivers in the championship.
If you are curious you can see the stats for any player who was rostered on at least 30% of teams below:
Some other fun finds
Having your first player bust is really hard to recover from. Whether it was Christian McCaffrey (9% chance at the championship), Saquon Barkley (1.9% chance at the championship), Michael Thomas (4.1% chance at the championship), or Clyde Edwards Helaire (5.5% chance at the championship), having your top pick fail to perform that way is devastating.
Alvin Kamara obviously came up huge in championship week (with 67% of Kamara owners who made the championship-winning it all), but he was actually second to Stefon Diggs (67.5%).
Handcuff players were common on championship rosters, Alexander Mattison gave managers a 19.3% chance of winning the championship (12th best), and Latavius Murray owners who made the championship won 64.2% of the time (4th best). (Note this does not mean that managers started these players, just that they were on the roster. They were likely indicators of Cook and Kamara respectively)
One major limitation to all of this analysis is it is only a snapshot based on what rosters looked like at the end of the playoffs. Players get hurt, contract covid, get suspended, etc, and miss the playoffs. In redraft leagues (which most of these are), there is no point in holding a player who has no chance of playing this year. So some numbers will be off (towards not being rostered) because of this. Additionally, I did not account for league competitiveness, so there could be some noise because of this.