Win probability

Saturday, 29 August 2026

16 matches selected · 14 tournaments · model last ran 19:50 UTC

Umpiry rates 16 matches on Saturday, 29 August 2026. The closest is Joaquin Aguilar Cardozo v Gonzalo Villanueva at 50 % — the model’s most uncertain call of the day. The most one-sided is Arthur Fery v James Duckworth at 71 %. 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
17:00M15 Mar Del Plata
ITF · clay
SFAguilar Cardozo J.Villanueva G.50 %50 %Toss-up3–2
21:00Philly Open - Philadelphia
CHALLENGER · hard
FVolynets K.Valentova T.51 %49 %Toss-up1–1
17:00M15 Champaign
ITF · hard
SFVrba J.Okonkwo O.51 %49 %Toss-up1–0
13:00W35 Verbier 2
ITF · clay
SFOkutoyi A.Ryser V.52 %48 %Toss-up1–0
12:00W75 Bytom
ITF · clay
SFHodzic M.Palicova B.52 %48 %Toss-up0–1
08:00M15 Maanshan
ITF · hard
SFZhang T.Aguiard E.52 %48 %Toss-up1–0
14:35Roehampton 2
CHALLENGER · hard
FLoffhagen G.Broom C.53 %47 %Toss-up2–0
11:00M15 Pecs
ITF · clay
SFHallquist Lithen J.Monzon I.54 %46 %Toss-up0–1
13:30M25 Lausanne
ITF · clay
SFCarboni L.Chepelev A.54 %46 %Toss-up0–2
13:00M15 Allershausen
ITF · clay
SFFilip J.Mueller C.55 %45 %Toss-up0–1
02:00Monterrey
WTA · hard
SFLi A.Parry D.55 %45 %Toss-up1–2
13:45M25 Oldenzaal
ITF · clay
SFWiedenmann L.Wessels L.57 %43 %Toss-up0–1
04:00Monterrey
WTA · hard
SFMertens E.Bartunkova N.59 %41 %Slight edge2–1
23:00Winston-Salem
ATP · hard
FFery A.Buse I.64 %36 %Slight edge2–1
12:45M25 Oviedo
ITF · clay
FRitschard A.Perez Contri S.65 %35 %Slight edge3–0
02:00Winston-Salem
ATP · hard
SFFery A.Duckworth J.71 %29 %Clear favourite2–2

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

Friday, 28 August 2026 · 20 matches

Favourites won

10 / 20

Model expected

11.3

The model expected 11.3 favourites to win; 10 did. See yesterday’s page.

Biggest shock, last 7 days

27 Aug
M15 Pecs
ITF · clay
R16

Surprise score

89

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.