Primera Division · Sunday, 26 April 2026. Final score 0–1 (half-time 0–1). Rebuilt from the season as it stood that morning, our rating would have been 42% for over 2.5 goals. This match is older than our frozen ratings ledger, which keeps 30 days, so that figure is a reconstruction from pre-match data rather than a number we published at the time — a distinction worth making, because only the frozen ones prove what we actually said beforehand.
Open this match in the app →| Market | Yes | No | Our call |
|---|---|---|---|
| Over 2.5 goals | 42% | 58% | Under |
| Over 3.5 goals | 20% | 80% | no pick |
| Both teams to score | 46% | 54% | No |
The result model puts Atletico Grau at 34%, the draw at 36% and Alianza Lima at 30%, from expected goals of 0.84 and 0.78.
The league sets the starting point. Primera Division has produced over 2.5 goals in 52% of its matches, and that is where a team with no record of its own would sit.
Each side's own record. Atletico Grau have 4 in 11 this season (2 of 5 at home), Alianza Lima 4 in 11 (1 of 6 away). Those records are pulled toward the league rate with the weight of about 24 matches — enough that two or three unusual games cannot swing a rating — giving 47% and 47%.
Last season still counts, briefly. With 11 and 11 games played this season, last season's rates are still blended in and fade out entirely by game 40 — the point at which our testing showed they stop adding accuracy. A single season is part luck, so each club's record is first pulled toward the league average by 34 games' weight. That moves the two figures to 48% and 49%.
The mix. Weighted 40% home side, 40% away side and 20% league — the split that beat every alternative across 30,582 matches of testing — that gives 49%.
Head to head. These sides have met 5 times in three years, producing over 2.5 goals in 20%. That nudges the number 5% of the way toward the head-to-head pattern — deliberately small, because fixtures change more than reputations do — landing on 48%.
Goal expectation. Separately a Poisson model built from attack and defence strength — using real expected-goals data where the league has it — puts this match at 22%, from expected goals of 0.84 for Atletico Grau and 0.78 for Alianza Lima. Folding in 30% of that view gives 40%.
Calibration. Tested against 97,729 past matches, our ratings below 55% have run consistently too pessimistic — a figure in the high 30s, for instance, has come in about four points higher. So ratings in that range are lifted part-way back, giving 42%.
This breakdown is generated from the same inputs the rating uses, so it cannot describe a calculation we did not perform. The full model is set out in the methodology.
| Team | Games | O2.5 | O3.5 | BTTS |
|---|---|---|---|---|
| Atletico Grau | 11 | 36% | 27% | 36% |
| Alianza Lima | 11 | 36% | 18% | 36% |
More: Atletico Grau season stats · Alianza Lima season stats · Primera Division table and form. Ratings are calibrated probabilities, not tips — a 60% call is expected to miss two times in five.