Week 2 2025 · September 6, 2025
Illinois at Duke, Week 2 2025: who deserved to win?
Illinois beat Duke 45–19, but the replays call it close to a coin flip: with the way both teams played, Illinois wins 5 of 10. Luck ran its way: fumble bounces alone were worth 14 points of win probability to Illinois.
Before kickoff Illinois was a 56% favorite. The biggest swing (Q3, 13:25 left): Illegal Substitution on Duke, 5 yards, worth 10 points of win probability to Illinois.
Final
 Illinois Fighting Illini | 45 |
|---|---|
 Duke Blue Devils | 19 |
Replay with same day's form
Luck index +53 Illinois lucky · −53 Duke
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. Illinois wins 5, Duke wins 5.
- 1 ILL 45 DUKE 21
- 2 ILL 31 DUKE 14
- 3 ILL 28 DUKE 17
- 4 ILL 28 DUKE 21
- 5 ILL 10 DUKE 7
- 6 ILL 17 DUKE 20
- 7 ILL 27 DUKE 33
- 8 ILL 16 DUKE 27
- 9 ILL 21 DUKE 38
- 10 ILL 31 DUKE 56
Three other ways to ask
Each answers a different question, so none of them replaces the replay above.
Before kickoff
The closing betting line, turned into a probability. What everyone knew before the game.
Same teams, fresh 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.
Only coin-flips re-rolled
Every kick, fumble bounce, conversion and judgment call redrawn; everything else fixed. The narrowest view of luck.
How 4,000 replays ended
Illinois wins 47% of them, Duke 53%, counting the 5% still level after regulation as half each. The line is what actually happened: Illinois by 26.
Show as a table
| Final margin in the replays | Share of replays |
|---|---|
| Illinois by 17+ | 11.2% |
| Illinois by 9–16 | 11.7% |
| Illinois by 1–8 | 19.1% |
| Level after regulation | 5.3% |
| Duke by 1–8 | 20.9% |
| Duke by 9–16 | 15.3% |
| Duke by 17+ | 16.4% |
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.
The kicks
How likely each kicker was to make that kick (his own record, the distance), and what happened.
- T. Pelino, 40 yds made · 73% expected
- T. Pelino, 40 yds made · 74% expected
- D. Olano, 35 yds made · 82% expected
Penalties: Illinois 7 for 51 yards, Duke 6 for 69 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
| When | Flag | Win probability for |
|---|---|---|
| Q1 14:40 | Face Mask on Illinois, 15 yards | +2% DUKE +0.9 pts |
| Q1 6:10 | Pass Interference on Duke, 14 yards | +7% ILL +3.1 pts |
| Q1 4:33 | False Start on Illinois, 5 yards · pre-snap | +1% DUKE +0.5 pts |
| Q2 14:50 | Illegal Substitution on Illinois, 5 yards · pre-snap | +1% DUKE +0.6 pts |
| Q2 12:07 | Pass Interference on Duke, 15 yards | +1% ILL +0.4 pts |
| Q2 11:17 | Delay of Game on Duke, 5 yards · pre-snap | 0% ILL +0.2 pts |
| Q2 11:03 | False Start on Illinois, 5 yards · pre-snap | +2% DUKE +0.7 pts |
| Q2 6:11 | Holding on Illinois, 10 yards | +3% DUKE +1.5 pts |
| Q2 3:48 | Roughing the Passer on Duke, 15 yards | +2% ILL +1.2 pts |
| Q2 0:14 | Roughing the Passer on Illinois, 6 yards | +5% DUKE +2.2 pts |
| Q3 13:25 | Illegal Substitution on Duke, 5 yards · pre-snap | +10% ILL +3.6 pts |
| Q3 7:20 | Roughing the Passer on Duke, 15 yards | +3% ILL +1.6 pts |
| Q4 14:19 | False Start on Illinois, 5 yards · pre-snap | +1% DUKE +0.7 pts |
When it happened
Duke’s chance of winning
As low as 0% and as high as 55%. Numbers mark the biggest luck moments, listed below.
| # | When | What happened | Win probability for | Next drive |
|---|---|---|---|---|
| 1 | Q1 6:10 | Pass Interference on Duke, 14 yardsJudgment calls | +7% ILL | ILL: Touchdown |
| 2 | Q1 4:05 | Duke fumbled and Illinois recoveredFumble bounces · loose balls are close to 50/50 | +7% ILL | DUKE: Field goal |
| 3 | Q1 2:30 | Illinois converted 3rd & 63rd & 4th downs · 41% expected | +4% ILL | ILL: Touchdown |
| 4 | Q2 10:14 | Illinois converted 3rd & 213rd & 4th downs · 18% expected | +8% ILL | ILL: Touchdown |
| 5 | Q2 5:01 | Illinois converted 3rd & 83rd & 4th downs · 29% expected | +6% ILL | ILL: Punt |
| 6 | Q2 0:14 | Roughing the Passer on Illinois, 6 yardsJudgment calls | +5% DUKE | DUKE: Touchdown |
| 7 | Q3 13:25 | Illegal Substitution on Duke, 5 yardsPre-snap flags | +10% ILL | ILL: Touchdown |
| 8 | Q3 8:00 | Duke fumbled and Illinois recoveredFumble bounces · loose balls are close to 50/50 | +4% ILL | DUKE: Touchdown |
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
Illinois 100% · Duke 0%
- Final margin
- Illinois by 26
- Luck in points
- 5.5 for Illinois
- Luck-adjusted margin
- Illinois by 20.5
- Replay with same day's form
- Illinois 47% · Duke 53% unchanged: why
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 2 2025 games · 
Illinois · 
Duke
More from Week 2 2025
- Boston College at Michigan State MSU 42–40 · replay 8% for the winner
- Baylor at SMU BAY 48–45 · replay 27% for the winner
- Miami (OH) at Rutgers RUTG 45–17 · replay 46% for the winner
- Iowa at Iowa State ISU 16–13 · replay 52% for the winner
- UCLA at UNLV UNLV 30–23 · replay 64% for the winner
- UConn at Syracuse SYR 27–20 · replay 66% for the winner
- North Carolina at Charlotte UNC 20–3 · replay 76% for the winner
- James Madison at Louisville LOU 28–14 · replay 77% for the winner
- Troy at Clemson CLEM 27–16 · replay 79% for the winner
- Western Illinois at Northwestern NU 42–7 · replay 80% for the winner
- Michigan at Oklahoma OU 24–13 · replay 84% for the winner
- Virginia at NC State NCSU 35–31 · replay 84% for the winner