luckadjusted
CFB Week 4 · 2026

Week 4 2025 · September 20, 2025

Coastal Carolina at South Alabama, Week 4 2025: who deserved to win?

Coastal Carolina beat South Alabama 38–20, and the replays lean its way: with the same day's form, it wins 7 of 10.

An off day for South Alabama: its offense played far below its usual level. In a fresh game against Coastal Carolina it would win 76% of the time; with this day’s form, 26%. The numbers

Before kickoff South Alabama was an 83% favorite.

Final

Coastal Carolina Chanticleers 38
South Alabama Jaguars 20

September 20, 2025 · Hancock Whitney Stadium · Closing line: South Alabama −14.5

Luck index +26 Coastal Carolina lucky · −26 South Alabama

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. Coastal Carolina wins 7, South Alabama wins 3.

  1. 1 CCU 47 USA 10
  2. 2 CCU 26 USA 0
  3. 3 CCU 35 USA 15
  4. 4 CCU 38 USA 21
  5. 5 CCU 26 USA 13
  6. 6 CCU 27 USA 20
  7. 7 CCU 24 USA 21
  8. 8 CCU 28 USA 31
  9. 9 CCU 20 USA 28
  10. 10 CCU 7 USA 27

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.

An off day for South Alabama

Its offense played far below its usual level. In a fresh game against Coastal Carolina it would win 76% of the time; with this day’s form, 26%.

50 points apart for South Alabama: the gap is how differently this game went from what the two teams usually are.

UnitThis gameUsual levelBetter or worse than usual
Coastal Carolina offenseEPA per play gained +0.12 +0.08 better by 0.04
Coastal Carolina defenseEPA per play allowed +0.07 +0.07 better by 0.00
South Alabama offenseEPA per play gained +0.07 +0.20 worse by 0.13
South Alabama defenseEPA per play allowed +0.12 +0.09 worse by 0.03

EPA (expected points added) per play on competitive snaps, turnovers left out because they are valued as luck. Usual level: the team’s earlier games this season plus half of last season, pulled toward the league average. One team’s defense and the other team’s offense are the same snaps, so one game can’t fully say whose day it was; it shows how far this one was from both teams’ norms.

How 4,000 replays ended

Coastal Carolina wins 74% of them, South Alabama 26%, counting the 4% still level after regulation as half each. The line is what actually happened: Coastal Carolina by 18.

Show as a table
Final margin in the replaysShare of replays
Coastal Carolina by 17+34.5%
Coastal Carolina by 9–1618.0%
Coastal Carolina by 1–819.1%
Level after regulation3.8%
South Alabama by 1–813.2%
South Alabama by 9–167.0%
South Alabama by 17+4.4%

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.

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 +4.9 points to Coastal Carolina: the final margin was Coastal Carolina by 18, without the luck Coastal Carolina by 13.1. 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.

  • H. DiBoyan, 37 yds made · 78% expected
  • H. DiBoyan, 33 yds missed · 84% expected
  • H. DiBoyan, 47 yds made · 59% expected
  • K. Afrookhteh, 44 yds made · 65% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: Coastal Carolina 6 for 44 yards, South Alabama 8 for 70 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 12:43 False Start on South Alabama, 5 yards · pre-snap +1% CCU +0.7 pts
Q1 0:46 Holding on South Alabama, 10 yards +3% CCU +1.8 pts
Q2 14:54 Illegal Motion on Coastal Carolina, 5 yards · pre-snap +1% USA +0.8 pts
Q3 6:56 Pass Interference on Coastal Carolina, 15 yards +6% USA +2.1 pts
Q3 4:17 Face Mask on South Alabama, 15 yards +8% CCU +2.2 pts
Q3 2:35 Delay of Game on Coastal Carolina, 5 yards · pre-snap +4% USA +1.3 pts
Q3 0:56 False Start on South Alabama, 5 yards · pre-snap +4% CCU +0.7 pts
Q4 10:35 Offside on South Alabama, 5 yards · pre-snap +5% CCU +0.9 pts
Q4 10:09 Roughing the Passer on South Alabama, 15 yards 0% CCU +0.7 pts
Q4 8:58 Offside on Coastal Carolina, 5 yards · pre-snap +3% USA +0.8 pts
Q4 7:13 Illegal Snap on South Alabama, 5 yards · pre-snap +2% CCU +0.5 pts
Q4 5:04 False Start on Coastal Carolina, 5 yards · pre-snap +1% USA +0.5 pts
Q4 2:53 Intentional Grounding on Coastal Carolina, 9 yards +1% USA +2.0 pts
Q4 2:26 Holding on South Alabama, 10 yards 0% CCU +0.8 pts

When it happened

South Alabama’s chance of winning

As low as 0% and as high as 91%. 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 South Alabama was ahead in it, below while Coastal Carolina was.
#WhenWhat happenedWin probability forNext drive
1 Q3 11:19 Coastal Carolina converted 3rd & 73rd & 4th downs · 30% expected +7% CCU CCU: Punt
2 Q3 6:56 Pass Interference on Coastal Carolina, 15 yardsJudgment calls +6% USA USA: Field goal
3 Q3 4:17 Face Mask on South Alabama, 15 yardsJudgment calls +8% CCU CCU: Punt
4 Q3 2:35 Delay of Game on Coastal Carolina, 5 yardsPre-snap flags +4% USA USA: Missed field goal
5 Q4 14:46 South Alabama converted 3rd & 63rd & 4th downs · 39% expected +8% USA USA: Missed field goal
6 Q4 13:01 South Alabama was stopped on 3rd & 63rd & 4th downs · 40% expected +6% CCU USA: Missed field goal
7 Q4 10:35 Offside on South Alabama, 5 yardsPre-snap flags +5% CCU CCU: Touchdown
8 Q4 10:25 Coastal Carolina converted 3rd & 43rd & 4th downs · 50% expected +7% CCU CCU: 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

Coastal Carolina 98% · South Alabama 2%

Final margin
Coastal Carolina by 18
Luck in points
4.9 for Coastal Carolina
Luck-adjusted margin
Coastal Carolina by 13.1
Replay with same day's form
Coastal Carolina 74% · South Alabama 26% 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 2025 games · Coastal Carolina · South Alabama

More from Week 4 2025

Every week 4 game, 2025