Win probability

Thursday, 3 September 2026

20 matches selected · 2 tournaments · model last ran 21:50 UTC

Umpiry rates 20 matches on Thursday, 3 September 2026. The closest is Arthur Gea v Zachary Svajda at 51 % — the model’s most uncertain call of the day. The most one-sided is Aryna Sabalenka v Polina Iatcenko at 96 %. 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
00:15US Open
ATP · hard
R64Gea A.Svajda Z.51 %49 %Toss-up1–0
22:00US Open
WTA · hard
R64Sakatsume H.Bucsa C.52 %48 %Toss-up0–1
23:00US Open
ATP · hard
R64Bonzi B.Buse I.55 %45 %Toss-up1–1
23:50US Open
ATP · hard
R128De Jong J.Passaro F.55 %45 %Toss-up3–0
21:00US Open
ATP · hard
R64Tabilo A.Popyrin A.55 %45 %Toss-up1–1
18:00US Open
ATP · hard
R64Darderi L.Svrcina D.62 %38 %Slight edge4–2
23:20US Open
ATP · hard
R64Wu Y.Duckworth J.69 %31 %Clear favourite1–0
18:00US Open
ATP · hard
R64Cerundolo F.Lennard Struff J.73 %27 %Clear favourite2–0
23:20US Open
ATP · hard
R64Berrettini M.Navone M.73 %27 %Clear favourite3–2
04:00US Open
WTA · hard
R64Noskova L.Tararudee L.74 %26 %Clear favourite1–0
01:20US Open
WTA · hard
R128Jovic I.Frech M.75 %25 %Clear favourite1–0
21:00US Open
ATP · hard
R64Cobolli F.Schoolkate T.78 %22 %Clear favourite1–0
18:00US Open
ATP · hard
R64Auger Aliassime F.Khachanov K.79 %21 %Clear favourite2–3
18:30US Open
WTA · hard
R64Osaka N.Siniakova K.82 %18 %Strong favourite3–1
19:30US Open
WTA · hard
R64Anisimova A.Tagger L.83 %17 %Strong favourite1–0
20:00US Open
WTA · hard
R64Eala A.Oliynykova O.83 %17 %Strong favourite1–1
04:05US Open
WTA · hard
R64Svitolina E.Joint M.86 %14 %Strong favourite1–0
18:00US Open
WTA · hard
R64Swiatek I.Podoroska N.95 %5 %Strong favourite2–0
03:30US Open
ATP · hard
R64Alcaraz C.Faria J.95 %5 %Strong favourite1–0
02:15US Open
WTA · hard
R64Sabalenka A.Iatcenko P.96 %4 %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

Wednesday, 2 September 2026 · 20 matches

Favourites won

16 / 20

Model expected

12.7

The model expected 12.7 favourites to win; 16 did. See yesterday’s page.

Biggest shock, last 7 days

2 Sept
W50 Leiria
ITF · hard
R32

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.