luckadjusted
CFB Week 4 · 2026

Week 4 2026 · September 26, 2026

Vanderbilt at Auburn, Week 4 2026: who deserved to win?

Auburn beat Vanderbilt 21–15, and the replays lean its way: with the same day's form, it wins 7 of 10.

Before kickoff Auburn was a 74% favorite. The biggest swing (Q2, 8:56 left): Return touchdown by Auburn, worth 8 points of win probability to Auburn.

Final

Vanderbilt Commodores 15
Auburn Tigers 21

September 26, 2026 · Jordan-Hare Stadium · Closing line: Auburn −10

Luck index +33 Auburn lucky · −33 Vanderbilt

Each team’s own plays from this game, resampled into new drives 4,000 times: with the way both teams actually played, how often does this performance win? How the replay works

Ten replays. Vanderbilt wins 3, Auburn wins 7.

  1. 1 VAN 27 AUB 10
  2. 2 VAN 17 AUB 10
  3. 3 VAN 20 AUB 17
  4. 4 VAN 14 AUB 17
  5. 5 VAN 3 AUB 7
  6. 6 VAN 14 AUB 21
  7. 7 VAN 7 AUB 17
  8. 8 VAN 0 AUB 13
  9. 9 VAN 10 AUB 27
  10. 10 VAN 0 AUB 24

Three other ways to ask

Each answers a different question, so none of them replaces the replay above.

The closing betting line, turned into a probability. What everyone knew before the game.

The line plus what this game showed, weighted by how much one game can tell. It stays close to the line because one game says little.

Every kick, fumble bounce, conversion and judgment call redrawn; everything else fixed. The narrowest view of luck.

How 4,000 replays ended

Vanderbilt wins 33% of them, Auburn 67%, counting the 6% still level after regulation as half each. The line is what actually happened: Auburn by 6.

Show as a table
Final margin in the replaysShare of replays
Vanderbilt by 17+3.9%
Vanderbilt by 9–168.2%
Vanderbilt by 1–816.6%
Level after regulation6.1%
Auburn by 1–825.7%
Auburn by 9–1619.6%
Auburn by 17+20.0%

Where the luck was

What the luck was worth

Every lucky and unlucky play, weighted by the moment it happened: its swing in win probability, added up by kind. A missed kick in a decided game counts for nothing; the same kick at the end of a tie game can be most of a win.

Swings add up across a game, so in one that went back and forth they can pass 100%. On the scoreboard the same luck was worth +4.2 points to Auburn: the final margin was Auburn by 6, without the luck Auburn by 1.8. Luck shares are the fitted ones (how much of each kind is luck).

The kicks

How likely each kicker was to make that kick (his own record, the distance), and what happened.

  • B. Taylor, 39 yds made · 80% expected
  • B. Taylor, 48 yds blocked · 63% expected
  • A. McPherson, 61 yds missed · 40% expected
  • B. Taylor, 47 yds made · 65% expected
  • B. Taylor, 45 yds made · 68% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Vanderbilt 8 for 55 yards, Auburn 5 for 44 yards

Every accepted flag, in order, and what it did to the helped team’s chance of winning at that moment, including any play it wiped out (points on the scoreboard in grey). A flag in a decided game is worth nothing; one at the turn of a close game can be worth most of a win. Judgment calls count toward luck, pre-snap fouls mostly don’t. How calls are valued

WhenFlagWin probability for
Q1 11:28 False Start on Vanderbilt, 5 yards · pre-snap +2% AUB +0.9 pts
Q1 4:02 Running Into the Kicker on Vanderbilt, 5 yards +1% AUB +0.6 pts
Q2 9:12 False Start on Vanderbilt, 5 yards · pre-snap +2% AUB +1.0 pts
Q2 7:24 Intentional Grounding on Vanderbilt, 12 yards +1% AUB +0.7 pts
Q2 4:45 Holding on Auburn, 10 yards +2% VAN +1.4 pts
Q3 7:26 Personal Foul on Auburn, 4 yards +2% VAN +1.0 pts
Q3 4:47 Pass Interference on Vanderbilt, 8 yards +1% AUB +1.1 pts
Q3 0:38 False Start on Vanderbilt, 5 yards · pre-snap +1% AUB +0.8 pts
Q3 0:17 Holding on Auburn, 10 yards +2% VAN +1.3 pts
Q3 0:14 Offside on Auburn, 5 yards · pre-snap +2% VAN +1.2 pts
Q4 12:26 Illegal Substitution on Vanderbilt, 5 yards · pre-snap +1% AUB +0.8 pts
Q4 9:38 Holding on Vanderbilt, 10 yards +2% AUB +1.2 pts
Q4 8:15 Roughing the Passer on Auburn, 15 yards +2% VAN +0.9 pts

When it happened

Auburn’s chance of winning

Numbers mark the biggest luck moments, listed below.

Our in-game win probability: the score, the value of the possession and the time left, starting from the betting line. Overtime has no clock and is drawn at a fixed width. Shaded above the middle while Auburn was ahead in it, below while Vanderbilt was.
#WhenWhat happenedWin probability forNext drive
1 Q1 8:26 Auburn converted 3rd & 53rd & 4th downs · 44% expected +3% AUB AUB: Touchdown
2 Q1 2:23 Vanderbilt converted 3rd & 93rd & 4th downs · 29% expected +3% VAN VAN: Turnover on downs
3 Q2 14:55 Vanderbilt was stopped on 4th & 53rd & 4th downs · 41% expected +3% AUB VAN: Punt
4 Q2 8:56 Return touchdown by AuburnSpecial teams +8% AUB AUB: Punt
5 Q3 5:35 Auburn converted 3rd & 73rd & 4th downs · 36% expected +4% AUB AUB: Touchdown
6 Q4 14:26 Vanderbilt converted 4th & 43rd & 4th downs · 46% expected +4% VAN VAN: Field goal
7 Q4 8:35 Vanderbilt converted 3rd & 113rd & 4th downs · 25% expected +5% VAN VAN: Field goal
8 Q4 4:52 Auburn converted 3rd & 53rd & 4th downs · 44% expected +4% AUB AUB: End of game

Adjust the assumptions

Disagree with how much of a fumble bounce or a pass interference call is luck? Change it and the coin-flip replay reruns in your browser.

Only coin-flips re-rolled

Vanderbilt 41% · Auburn 59%

Final margin
Auburn by 6
Luck in points
4.2 for Auburn
Luck-adjusted margin
Auburn by 1.8
Replay with same day's form
Vanderbilt 33% · Auburn 67% unchanged: why
How much of each is luck?

0% treats it as skill, 100% as pure luck. The tick is our fit.

What counts

None by default: our tests measured no carryover after a lucky break. Slide it up to count a break for more than its own swing. Why

Flip a play

Force the other outcome, in this game and in every replay: a made kick becomes a miss, a stop becomes a conversion, a flag goes the other way.

About these numbers

Play-by-play and expected points from CollegeFootballData.com via cfbfastR; win probability from our own model of the score, the possession and the betting line; kicks valued against each kicker’s own record. College play-by-play has no charting of drops or interception-worthy throws and no injury reports, so those kinds of luck aren’t counted here.

Methodology and validation · All Week 4 2026 games · Vanderbilt · Auburn

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