luckadjusted
NFL Week 9 · 2026

Week 1 2019 · September 8, 2019

No FTN charting for this game (drops and interception-worthy throws are not modelled).

49ers at Buccaneers, Week 1 2019: who deserved to win?

The 49ers beat the Buccaneers 31–17, but the replays call it close to a coin flip: with the way both teams played, the 49ers win 6 of 10.

Before kickoff it was a pick’em. The biggest swing (Q2, 8:47 left): Return touchdown by the Buccaneers, worth 22 points of win probability to the Buccaneers.

Final

San Francisco 49ers 31
Tampa Bay Buccaneers 17

September 8, 2019 · Raymond James Stadium · Closing line: Buccaneers −1

Luck index +42 49ers lucky · −42 Buccaneers

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. 49ers win 6, Buccaneers win 4.

  1. 1 SF 42 TB 17
  2. 2 SF 27 TB 10
  3. 3 SF 37 TB 24
  4. 4 SF 31 TB 23
  5. 5 SF 17 TB 13
  6. 6 SF 17 TB 15
  7. 7 SF 24 TB 27
  8. 8 SF 10 TB 17
  9. 9 SF 23 TB 34
  10. 10 SF 7 TB 26

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

49ers win 58% of them, Buccaneers 42%, counting the 4% still level after regulation as half each. The line is what actually happened: 49ers by 14.

Show as a table
Final margin in the replaysShare of replays
49ers by 17+13.2%
49ers by 9–1616.8%
49ers by 1–827.7%
Level after regulation3.6%
Buccaneers by 1–819.8%
Buccaneers by 9–1612.5%
Buccaneers by 17+6.3%

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 +4.0 points to the Buccaneers: the final margin was 49ers by 14, without the luck 49ers by 18. 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 the weather), and what happened.

  • R. Gould, 29 yds made · 96% expected
  • R. Gould, 36 yds made · 92% expected
  • R. Gould, 57 yds missed · 61% expected
  • M. Gay, 31 yds made · 95% expected
  • R. Gould, 47 yds made · 74% expected
Bar: expected chance of a make. Filled dot: made. Open dot: missed or blocked.

Penalties: 49ers 11 for 87 yards, Buccaneers 8 for 87 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 half toward luck; pre-snap fouls, which repeat, don’t count. How calls are valued

WhenFlagWin probability for
Q1 12:00 Offensive Pass Interference on the 49ers (Kyle Juszczyk), 10 yards, wiping out the play +7% TB +3.2 pts
Q1 10:27 Defensive Pass Interference on the 49ers (Richard Sherman), 16 yards +4% TB +1.7 pts
Q1 8:56 Defensive Holding on the 49ers (Richard Sherman), 5 yards +7% TB +1.7 pts
Q1 8:09 False Start on the Buccaneers (Jameis Winston), 5 yards · pre-snap +4% SF +0.8 pts
Q1 1:02 Disqualification on the 49ers (Kwon Alexander), 15 yards +6% TB +1.8 pts
Q2 13:45 Offensive Holding on the Buccaneers, 10 yards +2% SF +0.9 pts
Q2 12:10 Offensive Holding on the Buccaneers, 10 yards, wiping out the play +16% SF +4.0 pts
Q2 9:12 Illegal Block Above the Waist on the 49ers, 10 yards +3% TB +0.9 pts
Q2 6:21 Defensive Holding on the Buccaneers (Carlton Davis), 5 yards +10% SF +2.6 pts
Q2 4:38 Defensive Pass Interference on the Buccaneers (Vernon Hargreaves III), 9 yards +4% SF +1.2 pts
Q2 4:34 Offensive Holding on the 49ers (Richie James), 10 yards +2% TB +0.9 pts
Q2 3:46 Illegal Formation on the 49ers, 5 yards, wiping out the play · pre-snap +16% TB +4.1 pts
Q3 13:23 Defensive Pass Interference on the Buccaneers (Carlton Davis), 23 yards +13% SF +3.0 pts
Q4 15:00 Intentional Grounding on the Buccaneers (Jameis Winston), 10 yards +4% SF +0.9 pts
Q4 13:27 Neutral Zone Infraction on the 49ers (D.J. Jones), 2 yards · pre-snap +3% TB +0.3 pts
Q4 11:05 False Start on the 49ers (Deebo Samuel), 5 yards · pre-snap +2% TB +0.8 pts
Q4 9:29 Offensive Holding on the 49ers, 4 yards, wiping out the play +11% TB +2.1 pts
Q4 7:51 Defensive Offside on the 49ers (Solomon Thomas), 5 yards · pre-snap +1% TB +0.2 pts
Q4 3:22 Lowering the Head to Initiate Contact on the Buccaneers, 15 yards +5% SF +1.8 pts

49ers penalties, every game · Buccaneers penalties, every game · All teams, 2019

When it happened

Buccaneers’ chance of winning

As low as 0% and as high as 63%. 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 Buccaneers were ahead in it, below while the 49ers were.
#WhenWhat happenedWin probability forNext drive
1 Q2 12:10 Offensive Holding on the Buccaneers, 10 yards, wiping out the playJudgment calls +16% SF SF: Opp touchdown
2 Q2 8:47 Return touchdown by the BuccaneersSpecial teams +22% TB TB: Opp touchdown
3 Q2 3:46 Illegal Formation on the 49ers, 5 yards, wiping out the playPre-snap flags +16% TB TB: Turnover
4 Q3 13:23 Defensive Pass Interference on the Buccaneers (Carlton Davis), 23 yardsJudgment calls · no snap history yet +13% SF SF: Touchdown
5 Q3 11:53 Return touchdown by the 49ersSpecial teams +15% SF SF: Opp touchdown
6 Q4 13:07 The Buccaneers were stopped on 4th & 23rd & 4th downs · 51% expected +14% SF TB: Field goal
7 Q4 5:30 The Buccaneers were stopped on 3rd & 73rd & 4th downs · 25% expected +12% SF TB: Field goal
8 Q4 2:10 Return touchdown by the 49ersSpecial teams +17% SF SF: Opp touchdown

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.

  • Justin Evans (TB SS), out · 0.1 pts
  • Jimmie Ward (SF CB), out · 0.5 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

49ers 100% · Buccaneers 0%

Final margin
49ers by 14
Luck in points
4.0 for the Buccaneers
Luck-adjusted margin
49ers by 18.0
Replay with same day's form
49ers 58% · Buccaneers 42% 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 win probability from nflfastR via nflverse; kicks valued against each kicker’s own record; drops and interception-worthy throws from FTN charting (not available for this game); injuries from snap counts and injury reports. No FTN charting for this game (drops and interception-worthy throws are not modelled).

Methodology and validation · All Week 1 2019 games · 49ers · Buccaneers

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