Win probability

Tuesday, 4 August 2026

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

Umpiry rates 20 matches on Tuesday, 4 August 2026. The closest is Benjamin Bonzi v Yannick Hanfmann at 50 % — the model’s most uncertain call of the day. The most one-sided is Iga Swiatek v Sara Bejlek at 87 %. 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
22:45Montreal
ATP · hard
R128Bonzi B.Hanfmann Y.50 %50 %Toss-up0–1
21:50Toronto
WTA · hard
R64Rakhimova K.Siniakova K.50 %50 %Toss-up2–2
01:10Toronto
WTA · hard
R128Wang X.Kasatkina D.50 %50 %Toss-up0–2
20:50Montreal
ATP · hard
R64Munar J.Blockx A.51 %49 %Toss-up
19:05Montreal
ATP · hard
R128Medjedovic H.Cerundolo J.53 %47 %Toss-up3–1
23:50Montreal
ATP · hard
R128Diallo G.Jacquet K.54 %46 %Toss-up1–0
16:45Toronto
WTA · hard
R64Vekic D.Golubic V.55 %45 %Toss-up1–2
16:50Montreal
ATP · hard
R128Fearnley J.Mannarino A.55 %45 %Toss-up2–0
22:50Toronto
WTA · hard
R128Korpatsch T.Zarazua R.55 %45 %Toss-up0–3
16:40Toronto
WTA · hard
R64Osorio C.Alexandrova E.56 %44 %Toss-up3–1
17:05Montreal
ATP · hard
R128Shapovalov D.Svajda Z.56 %44 %Toss-up0–1
18:40Toronto
WTA · hard
R64Gibson T.Chwalinska M.57 %43 %Toss-up1–0
00:05Montreal
ATP · hard
R128Zheng M.Kecmanovic M.58 %42 %Toss-up0–1
21:50Toronto
WTA · hard
R64Kalinskaya A.Kessler M.61 %39 %Slight edge1–0
17:30Montreal
ATP · hard
R128Popyrin A.Burruchaga R.63 %37 %Slight edge1–0
22:45Toronto
WTA · hard
R128Lys E.Udvardy P.63 %37 %Slight edge1–2
20:20Montreal
ATP · hard
R64Rublev A.Shang J.65 %35 %Slight edge1–1
01:10Montreal
ATP · hard
R128Michelsen A.Lennard Struff J.72 %28 %Clear favourite2–0
15:10Toronto
WTA · hard
R64Svitolina E.Bouzas Maneiro J.77 %23 %Clear favourite4–0
16:40Toronto
WTA · hard
R64Swiatek I.Bejlek S.87 %13 %Strong favourite2–0

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, 3 August 2026 · 20 matches

Favourites won

11 / 20

Model expected

11.7

The model expected 11.7 favourites to win; 11 did. See yesterday’s page.

Biggest shock, last 7 days

2 Aug
Toronto
WTA · hard
R128

Surprise score

88

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.