Win probability

Monday, 7 September 2026

15 matches selected · 8 tournaments · model last ran 20:50 UTC

Umpiry rates 15 matches on Monday, 7 September 2026. The closest is Linang Xiao v Kaichi Uchida at 51 % — the model’s most uncertain call of the day. The most one-sided is Mirra Andreeva v Anastasia Potapova at 81 %. 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
13:00Shanghai
CHALLENGER · hard
R32Xiao L.Uchida K.51 %49 %Toss-up1–0
16:50Tulln
CHALLENGER · clay
R32Topo M.Elahi Galan D.51 %49 %Toss-up1–0
17:15Montreux Nestle Open - Montreux
CHALLENGER · clay
R32Curmi F.Brancaccio N.52 %48 %Toss-up1–1
16:35Genoa
CHALLENGER · clay
R32Ajdukovic D.Romano F.53 %47 %Toss-up1–0
23:30US Open
ATP · hard
R16Gea A.Van De Zandschulp B.53 %47 %Toss-up0–1
04:00US Open
WTA · hard
R16Kalinskaya A.Navarro E.54 %46 %Toss-up3–1
20:00US Open
ATP · hard
R16Cerundolo F.Blockx A.54 %46 %Toss-up0–2
13:20Istanbul
CHALLENGER · hard
R32Mayot H.Cretu C.56 %44 %Toss-up1–0
14:00Tulln
CHALLENGER · clay
R32Moeller M.Mrva M.57 %43 %Toss-up1–0
15:30Cassis
CHALLENGER · hard
R32Poullain L.Echargui M.58 %42 %Toss-up1–2
02:00US Open
ATP · hard
R16Shelton B.Tsitsipas S.71 %29 %Clear favourite1–1
00:25US Open
ATP · hard
R16Tien L.Khachanov K.72 %28 %Clear favourite0–1
22:55US Open
WTA · hard
R16Rybakina E.Osaka N.73 %27 %Clear favourite2–0
18:30US Open
WTA · hard
R16Swiatek I.Zheng Q.77 %23 %Clear favourite8–2
18:00US Open
WTA · hard
R16Andreeva M.Potapova A.81 %19 %Strong favourite6–2

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

Sunday, 6 September 2026 · 20 matches

Favourites won

11 / 20

Model expected

12.8

The model expected 12.8 favourites to win; 11 did. See yesterday’s page.

Biggest shock, last 7 days

6 Sept
W50 Evora
ITF · hard
Q32

Surprise score

80

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.