Game Theory in Fantasy Football: How to Win More Often by Thinking About What Your Opponents Will Do
Most fantasy managers optimize for the player most likely to score the most points. Game theory asks a different question: which player gives me the best chance to win specifically against my opponent this week, given what they are likely to do?
The distinction matters more often than you might think.
Game Theory Quick Reference
| Situation | Game theory action | Why | Mistake to avoid |
|---|---|---|---|
| You and your opponent both have the same RB | That player’s output is irrelevant to the matchup — focus decisions elsewhere | Shared players cancel each other out; their points neither help nor hurt you vs. this opponent | Celebrating a big game from a shared player — those points counted for both of you |
| Opponent has a stud WR likely to score 25+ pts | Pivot to higher-variance plays at your flex positions | You need a ceiling game to win — safe floors won’t beat a 25-pt WR advantage | Starting safe floors when your opponent’s ceiling is already locked above your projected floor |
| You need to make the playoffs and are a projected underdog | Accept more risk — boom/bust players over safe floors | A safe-floor lineup likely loses; a high-variance lineup at least gives you a chance | Playing it safe when safe is losing — the expected outcome is the same floor you already can’t win with |
| You’ve locked a playoff spot but your seed affects your bracket path | Evaluate which bracket draw gives you the best championship path | Sometimes the #4 seed’s path to the championship is easier than the #3 seed’s path | Automatically trying to win Week 14 when losing gets you a better bracket |
| Opponent needs a specific position; that player is on waivers | Block the add if you have waiver priority and it materially helps | You don’t improve your team, but you prevent a playoff rival from upgrading | Blocking positions your opponent doesn’t actually need — it wastes a waiver add |
| Tournament best ball — your lineup looks like everyone else’s | Add a contrarian low-ownership player with ceiling | In tournaments, winning requires a differentiated lineup; average builds share prize money | Optimizing for expected points when the format requires ceiling differentiation |
When Game Theory Applies
Shared players. The most direct game theory situation in fantasy is when you and your opponent have the same player. If you both start the same running back, his points cancel out — he contributes nothing to either team’s margin of victory. You should adjust your other start/sit decisions knowing one player is a wash.
Opponent’s key player. If your opponent has a stud WR who is going to produce 20+ points, your best path to victory might be to swing for high variance elsewhere — start boom-or-bust players rather than safe floors — because matching their expected ceiling is the only way to win.
When you need to win a specific week. Early in the season, safe floor players protect your record. But in Week 14 when you need to make the playoffs, game theory says to take calculated risks if safe decisions make you a likely loser.
Contrarian Strategy in Fantasy Football
What contrarian means. A contrarian pick is a player who is unlikely to be started by most managers but has high upside if he hits. In tournament formats (best ball, DFS), contrarian picks reduce score correlation with the field — if the contrarian player goes off, only you benefit.
In season-long leagues. Contrarian plays are less relevant in season-long leagues because you are only playing one opponent per week. But contrarian thinking still applies: if your opponent is clearly playing a safe lineup, a risky start that outperforms your opponent’s ceiling may be exactly right.
Playoff Bracket Positioning
Choosing your seeding. If you have locked a playoff spot but your seed still depends on Week 14 outcomes, consider which path through the playoff bracket gives you the best chance to win the championship. Sometimes losing a game in Week 14 to get a favorable bracket draw is worth more than winning to get an unfavorable bracket.
Strength of schedule. In leagues where playoff seeds determine opponents, game theory means evaluating which seed faces which teams. Seed 3 might face Seed 2 in the semifinals. Seed 4 might face Seed 1. If Seed 2 is clearly the best team and Seed 1 has matchup vulnerabilities you can exploit, seeding 4 might actually be preferable to seeding 3.
Game Theory in the Waiver Wire
Blocking opponents. If you know your opponent needs a specific position and a key player at that position is on the waiver wire, picking up that player even if you do not need them can be a legitimate game theory move. You are not improving your team — you are preventing your opponent from improving theirs.
When blocking makes sense. Blocking is most valuable when you have sufficient waiver priority to execute it and when your opponent’s need is acute (a position where their only starter is injured). Blocking random players your opponent does not need is a waste of adds.
For how game theory applies specifically to playoff fantasy decisions, see: Fantasy Football Streaming Strategy: How to Win With Waiver Wire Pickups at QB, DST, and K.