Win probability

Monday, 17 August 2026

15 matches selected · 2 tournaments · model last ran 19:50 UTC

Umpiry rates 15 matches on Monday, 17 August 2026. The closest is Ignacio Buse v Adam Walton at 52 % — the model’s most uncertain call of the day. The most one-sided is Elena Rybakina v Magdalena Frech at 90 %. Probabilities come from a per-tour model trained on Elo, surface Elo, recent serve and return form and layoff.

Rated matches · ordered closest first
TimeTournamentRoundMatchProbabilityVerdictH2H
22:45Cincinnati
ATP · hard
R64Buse I.Walton A.52 %48 %Toss-up1–1
17:45Cincinnati
WTA · hard
R32Cirstea S.Kalinskaya A.54 %46 %Toss-up3–1
15:10Cincinnati
WTA · hard
R32Parry D.Boisson L.56 %44 %Toss-up1–0
15:10Cincinnati
ATP · hard
R32Cobolli F.Blockx A.56 %44 %Toss-up1–2
15:10Cincinnati
ATP · hard
R32Tirante T.Landaluce M.57 %43 %Toss-up1–1
19:10Cincinnati
WTA · hard
R32Shnaider D.Chwalinska M.67 %33 %Clear favourite2–1
18:00Cincinnati
ATP · hard
R32De Minaur A.Fery A.70 %30 %Clear favourite1–0
21:40Cincinnati
ATP · hard
R32Jodar R.Tabilo A.71 %29 %Clear favourite2–1
02:10Cincinnati
ATP · hard
R64Tiafoe F.Sonego L.71 %29 %Clear favourite2–3
01:50Cincinnati
WTA · hard
R64Svitolina E.Valentova T.72 %28 %Clear favourite1–0
23:10Cincinnati
ATP · hard
R64Shelton B.Faria J.72 %28 %Clear favourite0–1
22:20Cincinnati
WTA · hard
R64Potapova A.Stephens S.76 %24 %Clear favourite1–1
15:10Cincinnati
WTA · hard
R32Swiatek I.Sakkari M.82 %18 %Strong favourite6–4
23:10Cincinnati
WTA · hard
R64Gauff C.Samsonova L.83 %17 %Strong favourite5–0
17:25Cincinnati
WTA · hard
R32Rybakina E.Frech M.90 %10 %Strong favourite4–0

How to read this

Each row gives the model’s probability that the favourite wins, and the verdict says the same thing in words. Rows are ordered by how close the model thinks the match is, so the top of the table is where it is least sure. A 70 % favourite losing is not a broken model — it is the 30 %. Probabilities are not odds and take no account of any market.

How often the model has been right

Umpiry win-probability model accuracy by tour family, measured on the predictions the model made
TourCorrect
ATP / WTA66 %
Challenger (men)64 %
Challenger (women)68 %
ITF (men)66 %
ITF (women)64 %

Measured on the predictions the model actually made, not on a backtest — see Methodology.

Yesterday

Sunday, 16 August 2026 · 20 matches

Favourites won

15 / 20

Model expected

13.2

The model expected 13.2 favourites to win; 15 did. See yesterday’s page.

Biggest shock, last 7 days

16 Aug
Cincinnati
WTA · hard
R64

Surprise score

93

Questions

How is the probability calculated?
A separate model for each tour, trained on Elo, surface-specific Elo, recent serve and return form and time since the player’s last match. It runs several times a day; the time of the last run is at the top of this page.
How often is the model right?
We publish it. The table above gives the hit rate for each tour family, measured on the predictions the model actually made — see Methodology for how it is computed.
Why are the closest matches at the top?
Rows are ordered by distance from 50 %, so the table opens where the model is least sure. “Most one-sided” reverses the order and groups the rows by tournament.
Is this a betting tip?
No. The page shows a model’s probability and how often that model has been right. There are no odds, no comparison with a market and no suggested stake.