Primera Nacional · Saturday, 29 August 2026. Final score 1–0 (half-time 0–0). Rebuilt from the season as it stood that morning, our rating would have been 32% 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 | 32% | 68% | Under |
| Over 3.5 goals | 11% | 89% | no pick |
| Both teams to score | 40% | 60% | No |
The result model puts Gimnasia Y Tiro at 50%, the draw at 32% and Chacarita Juniors at 18%, from expected goals of 1.19 and 0.59.
The league sets the starting point. Primera Nacional has produced over 2.5 goals in 30% of its matches, and that is where a team with no record of its own would sit.
Each side's own record. Gimnasia Y Tiro have 8 in 26 this season (2 of 13 at home), Chacarita Juniors 6 in 26 (2 of 13 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 30% and 26%.
Last season still counts, briefly. With 26 and 26 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 27%.
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 29%.
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 27%, from expected goals of 1.19 for Gimnasia Y Tiro and 0.59 for Chacarita Juniors. Folding in 30% of that view gives 28%.
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 32%.
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 |
|---|---|---|---|---|
| Gimnasia Y Tiro | 26 | 31% | 12% | 50% |
| Chacarita Juniors | 26 | 23% | 8% | 31% |
More: Gimnasia Y Tiro season stats · Chacarita Juniors season stats · Primera Nacional table and form. Ratings are calibrated probabilities, not tips — a 60% call is expected to miss two times in five.