Upset index
CONMEBOL Libertadores upset index
Matches won by the side the pre-match odds gave little chance, and which leagues and teams produce more upsets than expected. Index 100 = as many upsets as expected.
- Matches with a clear favourite
- 126
- Upsets
- 25
- Upset rate
- 19.8%
- Upset index
- 113
Filters
Odds data: 556,116 matches with a clear favourite between 31 Dec 2015 and 8 Nov 2026.
Biggest upsets
By the winner's pre-match chance (from odds) — lowest first
-
CONMEBOL Libertadores
Palmeiras0
Cerro Porteño1
Winner's pre-match chance 9.4% · odds 10.00
-
CONMEBOL Libertadores
CS 2 de Mayo1
Alianza Lima0
Winner's pre-match chance 10% · odds 9.00
-
CONMEBOL Libertadores
Cruzeiro1
Universidad Católica2
Winner's pre-match chance 13% · odds 7.50
-
CONMEBOL Libertadores
Boca Juniors0
Universidad Católica1
Winner's pre-match chance 13% · odds 7.00
-
CONMEBOL Libertadores
Universidad Católica del Ecuador3
Juventud de Las Piedras4
Penalties 3–4
Winner's pre-match chance 14% · odds 6.50
-
CONMEBOL Libertadores
Botafogo0
Barcelona SC Guayaquil1
Winner's pre-match chance 15% · odds 6.25
-
Argentinos Juniors
0–1
Barcelona SC Guayaquil
-
Club Atlético Peñarol
0–1
Independiente Santa Fe
-
Deportes Tolima
0–1
Deportivo Táchira
-
Libertad
0–1
Universidad Central
-
Corinthians
0–2
Club Atlético Platense
-
Palmeiras
0–1
Fluminense
-
Universidad Central
2–0
Independiente del Valle
-
Fluminense
1–2
Independiente Rivadavia
-
Club Atlético Peñarol
1–2
Club Atlético Platense
-
Guaraní
1–2
Juventud de Las Piedras
-
Corinthians
0–1
Estudiantes de La Plata
-
Huachipato
1–2
Carabobo FC
-
Barcelona SC Guayaquil
1–0
Boca Juniors
-
O'Higgins
1–0
Bahia
-
Club Sporting Cristal
1–2
Carabobo FC
-
Universitario de Deportes
0–2
Coquimbo Unido
-
Junior Barranquilla
0–1
Cerro Porteño
-
Barcelona SC Guayaquil
1–2
Universidad Católica
-
Club Always Ready
0–1
LDU
CONMEBOL Libertadores: by season
The most chaotic and most predictable seasons
Giant killers
Win more than expected as the underdog
| Team | Underdog wins | Expected | Index |
|---|---|---|---|
| Universidad Católica |
3/5 | 0.9 | 136 |
| Barcelona SC Guayaquil |
3/7 | 1.2 | 131 |
| Carabobo FC |
2/2 | 0.5 | 129 |
| Universidad Central |
2/5 | 0.6 | 125 |
| Cerro Porteño |
2/5 | 0.8 | 122 |
| Club Atlético Platense |
2/5 | 1.0 | 117 |
| Juventud de Las Piedras |
2/5 | 1.1 | 116 |
| Deportivo Táchira |
1/2 | 0.3 | 114 |
| Independiente Rivadavia |
1/2 | 0.4 | 112 |
| CS 2 de Mayo |
1/3 | 0.4 | 112 |
Upset victims
Lose more than expected as the favourite
| Team | Losses as favourite | Expected | Index |
|---|---|---|---|
| Club Atlético Peñarol |
2/3 | 0.6 | 125 |
| Boca Juniors |
2/5 | 0.9 | 119 |
| Libertad |
1/1 | 0.2 | 116 |
| Botafogo |
1/2 | 0.2 | 116 |
| Corinthians |
2/6 | 1.1 | 115 |
| Barcelona SC Guayaquil |
1/1 | 0.3 | 114 |
| Club Sporting Cristal |
1/2 | 0.4 | 112 |
| Palmeiras |
2/10 | 1.3 | 112 |
| Junior Barranquilla |
1/2 | 0.5 | 110 |
| Cruzeiro |
1/3 | 0.5 | 110 |
How is it calculated?
- Probability: From pre-match 1X2 (or two-way) odds, with the bookmaker margin removed proportionally: p = (1/odds) / Σ(1/odds). The same formula as the stats hub's “upsets by odds” block.
- Clear favourite and upset: Only matches with at least a 10-point gap between the home and away win probabilities count; if the favourite's opponent wins, it is an upset. Draws are not upsets. Winner's chance of 25% or less = big upset.
- Ranking: The lower the winner's pre-match chance, the bigger the upset (surprise score = 100 × (1 − chance)).
- Index: 100 × (actual upsets + 5) / (expected upsets + 5); expected = sum of the underdogs' win probabilities. The +5 pulls small samples towards 100. Teams have two directions: giant killing (winning as the underdog) and fragility (losing as the favourite).
- Calibration: Expected values are scaled by the source's overall hit factor (0.95 in this view), so a systematic bias of the source does not shift every league the same way.
- Historical (model): For past matches without odds, the probability comes from our learning Elo model replaying the full history chronologically and taking its state before the match (both teams need at least 15 matches; friendlies excluded). Never mixed with odds.