luckadjusted

Week 4 2025 · September 28, 2025

Colts at Rams, Week 4 2025: who deserved to win?

The Rams beat the Colts 27–20, and it was no fluke: replayed with the way both teams actually played, the Rams win 9 of 10. The Colts had the bounces: fumble bounces alone were worth 3.1 points to the Colts.

Before kickoff the Rams were 60% favorites. The biggest swing (Q4, 3:24 left): the Rams converted 4th & 2, worth 25 points of win probability to the Rams.

Final

Indianapolis Colts 20
Los Angeles Rams 27

September 28, 2025 · SoFi Stadium · Closing line: Rams −3.5

Luck index +14 Rams about even · −14 Colts

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. Colts win 1, Rams win 9.

  1. 1 IND 19 LA 13
  2. 2 IND 27 LA 30
  3. 3 IND 17 LA 22
  4. 4 IND 16 LA 24
  5. 5 IND 14 LA 26
  6. 6 IND 24 LA 38
  7. 7 IND 13 LA 31
  8. 8 IND 10 LA 31
  9. 9 IND 3 LA 29
  10. 10 IND 6 LA 40

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, drop, conversion and judgment call redrawn; everything else fixed. The narrowest view of luck.

How 4,000 replays ended

Colts win 14% of them, Rams 86%, counting the 2% still level after regulation as half each. The line is what actually happened: Rams by 7.

Show as a table
Final margin in the replaysShare of replays
Colts by 17+1.1%
Colts by 9–162.9%
Colts by 1–89.6%
Level after regulation1.5%
Rams by 1–819.4%
Rams by 9–1622.2%
Rams by 17+43.4%

Where the luck was

Take the luck out

The final margin was Rams by 7. Remove the luck, one kind at a time, and it becomes Rams by 8.5.

Each row takes one kind of luck out of the margin. Color shows which team it helped. Luck shares are the fitted ones (how much of each component is luck).

The kicks

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

  • J. Karty, 42 yds made · 86% expected
  • S. Shrader, 52 yds made · 71% expected
  • J. Karty, 37 yds made · 92% expected
  • S. Shrader, 38 yds made · 91% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

When it happened

Rams’ chance of winning

As low as 17% and as high as 100%. Numbers mark the biggest luck moments, listed below.

nflfastR’s in-game win probability. It ignores the betting line, so it starts near even. Shaded above the middle while the Rams were ahead in it, below while the Colts were.
#WhenWhat happenedWin probability forNext drive
1 Q2 8:37 The Rams converted 3rd & 53rd & 4th downs · 40% expected +9% LA LA: Field goal
2 Q4 11:29 The Rams fumbled and the Colts recoveredFumble bounces · loose balls are close to 50/50 +9% IND LA: Touchdown
3 Q4 11:22 Offensive Pass Interference on the Colts (Tyler Warren), 10 yards, wiping out the playJudgment calls · 0 flags in 159 snaps before, position avg 1 per 278 +8% LA LA: Touchdown
4 Q4 6:21 Offensive Holding on the Rams, 10 yards, wiping out the playJudgment calls +13% IND IND: Punt
5 Q4 4:09 The Rams got away with an interception-worthy throwInterceptions · 51% expected to stay out of the defense's hands +12% LA LA: Touchdown
6 Q4 3:24 The Rams converted 4th & 23rd & 4th downs · 51% expected +25% LA LA: Touchdown
7 Q4 3:20 Unnecessary Roughness on the Rams (Omar Speights), 15 yardsJudgment calls · 2 flags in 996 snaps before, position avg 1 per 445 +8% IND IND: Punt
8 Q4 2:10 The Colts fumbled and recovered it themselvesFumble bounces · loose balls are close to 50/50 +11% IND IND: Punt

Missing players

Key players (usually on the field for half the snaps or more) who missed this game or part of it, valued by position and quality. The same players are missing in every replay, so this counts as luck in points only.

  • Ahkello Witherspoon (LA CB), out (IR) · 0.4 pts
  • Beaux Limmer (LA C), out · 0.3 pts
  • Alec Pierce (IND WR), out · 0.8 pts
  • Matt Goncalves (IND T), out · 0.7 pts
  • Jaylon Jones (IND CB), out (IR) · 0.6 pts
  • Matt Goncalves (IND G), out · 0.4 pts

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

Colts 8% · Rams 92%

Final margin
Rams by 7
Luck in points
1.5 for the Colts
Luck-adjusted margin
Rams by 8.5
Replay with same day's form
Colts 14% · Rams 86% unchanged: why
How much of each is luck?

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

What counts

We tested momentum on 19,000 lucky breaks and found none, so it's off by default. 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 win probability from nflfastR via nflverse; kicks valued against each kicker’s own record; drops and interception-worthy throws from FTN charting; injuries from snap counts and injury reports.

Methodology and validation · All Week 4 2025 games · Colts · Rams

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