Win probability

Tuesday, 18 August 2026

20 matches selected · 2 tournaments · model last ran 20:50 UTC

Umpiry rates 20 matches on Tuesday, 18 August 2026. The closest is Sara Bejlek v Ekaterina Alexandrova at 51 % — the model’s most uncertain call of the day. The most one-sided is Elina Svitolina v Xiyu Wang at 95 %. 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
21:10Cincinnati
WTA · hard
R32Bejlek S.Alexandrova E.51 %49 %Toss-up2–0
15:10Cincinnati
ATP · hard
R32Rublev A.Borges N.55 %45 %Toss-up5–1
01:05Cincinnati
ATP · hard
R32Fils A.Lehecka J.60 %40 %Slight edge4–2
21:10Cincinnati
ATP · hard
R32Faria J.Walton A.62 %38 %Slight edge1–0
18:55Cincinnati
ATP · hard
R32Medvedev D.Nakashima B.62 %38 %Slight edge3–1
02:25Cincinnati
WTA · hard
R32Anisimova A.Eala A.68 %32 %Clear favourite1–0
16:55Cincinnati
ATP · hard
R32Musetti L.Zheng M.74 %26 %Clear favourite1–0
15:10Cincinnati
WTA · hard
R32Keys M.Siniakova K.75 %25 %Clear favourite3–0
22:45Cincinnati
WTA · hard
R32Noskova L.Tauson C.76 %24 %Clear favourite1–2
23:00Cincinnati
WTA · hard
R32Pegula J.Navarro E.77 %23 %Clear favourite6–0
16:45Cincinnati
ATP · hard
R32Fritz T.Merida Aguilar D.78 %22 %Clear favourite1–0
23:10Cincinnati
ATP · hard
R32Mensik J.Hijikata R.79 %21 %Clear favourite1–0
15:00Cincinnati
ATP · hard
R32Fonseca J.O'Connell C.81 %19 %Strong favourite
02:40Cincinnati
ATP · hard
R32Paul T.Vallejo A.84 %16 %Strong favourite2–0
19:10Cincinnati
WTA · hard
R32Gauff C.Li A.86 %14 %Strong favourite4–0
16:50Cincinnati
WTA · hard
R32Andreeva M.Tjen J.87 %13 %Strong favourite2–0
19:10Cincinnati
WTA · hard
R32Kostyuk M.Stephens S.90 %10 %Strong favourite2–0
23:45Cincinnati
ATP · hard
R32Zverev A.Atmane T.93 %7 %Strong favourite2–0
17:00Cincinnati
WTA · hard
R32Sabalenka A.Yu Wang X.94 %6 %Strong favourite2–0
18:30Cincinnati
WTA · hard
R32Svitolina E.Wang X.95 %5 %Strong favourite1–0

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

Monday, 17 August 2026 · 15 matches

Favourites won

12 / 15

Model expected

10.3

The model expected 10.3 favourites to win; 12 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.