Primera Nacional · Saturday, 23 May 2026. Final score 2–1 (half-time 1–0). Rebuilt from the season as it stood that morning, our rating would have been 35% 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 | 35% | 65% | Under |
| Over 3.5 goals | 13% | 87% | no pick |
| Both teams to score | 44% | 56% | No |
The result model puts San Martin S.J. at 37%, the draw at 30% and Deportivo Maipu at 34%, from expected goals of 1.16 and 1.09.
The league sets the starting point. Primera Nacional has produced over 2.5 goals in 28% of its matches, and that is where a team with no record of its own would sit.
Each side's own record. San Martin S.J. have 4 in 13 this season (2 of 6 at home), Deportivo Maipu 7 in 13 (5 of 7 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 29% and 37%.
Last season still counts, briefly. With 13 and 13 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 29% and 31%.
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 30%.
Head to head. These sides have met 3 times in three years, producing over 2.5 goals in 0%. 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 28%.
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 39%, from expected goals of 1.16 for San Martin S.J. and 1.09 for Deportivo Maipu. Folding in 30% of that view gives 31%.
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 35%.
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 |
|---|---|---|---|---|
| San Martin S.J. | 13 | 31% | 0% | 62% |
| Deportivo Maipu | 13 | 54% | 31% | 54% |
More: San Martin S.J. season stats · Deportivo Maipu season stats · Primera Nacional table and form. Ratings are calibrated probabilities, not tips — a 60% call is expected to miss two times in five.