Championship · Tuesday, 1 September 2026. Final score 0–2 (half-time 0–1). Rebuilt from the season as it stood that morning, our rating would have been 51% 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 | 51% | 49% | Over |
| Over 3.5 goals | 28% | 72% | no pick |
| Both teams to score | 57% | 43% | Yes |
The result model puts Portsmouth at 31%, the draw at 26% and Derby at 43%, from expected goals of 1.21 and 1.46.
The league sets the starting point. Championship 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. Portsmouth have 3 in 3 this season (1 of 1 at home), Derby 3 in 3 (1 of 1 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 58% and 58%.
Last season still counts, briefly. With 3 and 3 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 53%.
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 51%.
Head to head. These sides have met 4 times in three years, producing over 2.5 goals in 50%. 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 50%, from expected goals of 1.21 for Portsmouth and 1.46 for Derby. Folding in 30% of that view gives 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 |
|---|---|---|---|---|
| Portsmouth | 3 | 100% | 67% | 100% |
| Derby | 3 | 100% | 33% | 67% |
More: Portsmouth season stats · Derby season stats · Championship table and form. Ratings are calibrated probabilities, not tips — a 60% call is expected to miss two times in five.