Win probability

Tuesday, 11 August 2026

9 matches selected · 5 tournaments · model last ran 17:50 UTC

Umpiry rates 9 matches on Tuesday, 11 August 2026. The closest is Max Houkes v Sumit Nagal at 52 % — the model’s most uncertain call of the day. The most one-sided is Elina Svitolina v Ekaterina Alexandrova at 78 %. 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
14:40Hamburg
CHALLENGER · clay
R32Houkes M.Nagal S.52 %48 %Toss-up1–2
08:05Todi
CHALLENGER · clay
R32Emanuel Ambrogi L.Ajdukovic D.53 %47 %Toss-up1–0
10:40Hamburg
CHALLENGER · clay
R32Hans Rehberg M.Dedura D.54 %46 %Toss-up1–0
00:50Brownsburg
CHALLENGER · hard
R32Milavsky D.Balshaw F.55 %45 %Toss-up1–0
08:35Hamburg
CHALLENGER · clay
R32Krutykh O.Dietrich D.57 %43 %Toss-up0–1
18:20Montreal
ATP · hard
QFFils A.Jodar R.63 %37 %Slight edge1–2
16:40Montreal
ATP · hard
QFNakashima B.Darderi L.65 %35 %Slight edge2–1
23:10Toronto
WTA · hard
QFSwiatek I.Shnaider D.65 %35 %Slight edge2–0
00:30Toronto
WTA · hard
QFSvitolina E.Alexandrova E.78 %22 %Clear favourite4–2

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, 10 August 2026 · 6 matches

Favourites won

4 / 6

Model expected

3.7

The model expected 3.7 favourites to win; 4 did. See yesterday’s page.

Biggest shock, last 7 days

9 Aug
Toronto
WTA · hard
R16

Surprise score

92

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.