Serie A · Sunday, 20 September 2026. Final score 1–1 (half-time 0–1). Before kick-off we rated it 55% over 2.5 goals — the match finished with 2, so that call missed. That rating was frozen into a version-controlled ledger before the game and has not been touched since.
Open this match in the app →| Market | Yes | No | Our call |
|---|---|---|---|
| Over 2.5 goals | 51% | 49% | Over |
| Over 3.5 goals | 26% | 74% | no pick |
| Both teams to score | 50% | 50% | Yes |
The result model puts Fiorentina at 21%, the draw at 25% and Napoli at 53%, from expected goals of 0.93 and 1.63.
The league sets the starting point. Serie A has produced over 2.5 goals in 47% of its matches, and that is where a team with no record of its own would sit.
Each side's own record. Fiorentina have 4 in 4 this season (2 of 2 at home), Napoli 2 in 4 (1 of 2 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 54% and 47%.
Last season still counts, briefly. With 4 and 4 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 49% and 50%.
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 6 times in three years, producing over 2.5 goals in 100%. 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 51%.
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 47%, from expected goals of 0.93 for Fiorentina and 1.63 for Napoli. Folding in 30% of that view gives 50%.
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 51%.
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 |
|---|---|---|---|---|
| Fiorentina | 4 | 100% | 50% | 50% |
| Napoli | 4 | 50% | 25% | 50% |
More: Fiorentina season stats · Napoli season stats · Serie A table and form. Ratings are calibrated probabilities, not tips — a 60% call is expected to miss two times in five.