Win probability

Friday, 21 August 2026

20 matches selected · 14 tournaments · model last ran 18:50 UTC

Umpiry rates 20 matches on Friday, 21 August 2026. The closest is Lisa Zaar v Georgia Pedone at 50 % — the model’s most uncertain call of the day. The most one-sided is Arthur Fils v Thiago Agustin Tirante at 80 %. Probabilities come from a per-tour model trained on Elo, surface Elo, recent serve and return form and layoff.

Rated matches · ordered closest first
Time	Tournament	Round	Match	Probability	Verdict	H2H
09:00	W75 Kursumlijska Banja 3 ITF · clay	QF	Zaar L.Pedone G.	50 %50 %	Toss-up	1–0
11:50	W50 Prague ITF · clay	SF	Kotliar Y.Gao X.	50 %50 %	Toss-up	0–1
02:00	W15 Tianjin 3 ITF · hard	QF	Plipuech P.Zhu C.	51 %49 %	Toss-up	1–0
08:00	M15 Arad ITF · clay	QF	Guna R.Monzon I.	51 %49 %	Toss-up	1–0
12:25	Prague CHALLENGER · clay	SF	Jianu F.Kumstat J.	51 %49 %	Toss-up	0–1
15:10	Quebec City CHALLENGER · hard	QF	Van Assche L.Bonzi B.	51 %49 %	Toss-up	3–3
16:05	W35 Verbier ITF · clay	QF	Bonelli E.Grubor A.	52 %48 %	Toss-up	0–1
10:00	M25 Idanha-A-Nova 2 ITF · hard	QF	Scaglia M.Lagutin P.	52 %48 %	Toss-up	0–1
10:10	Roehampton CHALLENGER · hard	SF	Maxted L.Poullain L.	52 %48 %	Toss-up	0–1
02:00	M15 Maanshan 7 ITF · hard	QF	Takahashi Y.Isomura K.	54 %46 %	Toss-up	0–3
11:35	W35 Krakow ITF · clay	SF	Pawlikowska Z.Jakupovic D.	54 %46 %	Toss-up	0–4
08:00	M15 Arad ITF · clay	QF	Misasi G.Nicolae Madaras D.	54 %46 %	Toss-up	0–1
05:00	M15 Maanshan 7 ITF · hard	QF	Becroft I.Rifqi F.	55 %45 %	Toss-up	1–1
17:30	Quebec City CHALLENGER · hard	QF	De Jong J.Gaston H.	55 %45 %	Toss-up	0–2
22:55	Cancun 2 CHALLENGER · hard	R16	Harris L.Llamas Ruiz P.	57 %43 %	Toss-up	3–0
18:05	Cincinnati WTA · hard	QF	Pegula J.Anisimova A.	58 %42 %	Toss-up	7–0
23:10	Cincinnati WTA · hard	QF	Rybakina E.Swiatek I.	62 %38 %	Slight edge	7–9
19:20	Cincinnati ATP · hard	QF	Fritz T.Nakashima B.	67 %33 %	Slight edge	4–2
17:00	Cincinnati WTA · hard	QF	Keys M.Bejlek S.	69 %31 %	Clear favourite	0–1
00:40	Cincinnati ATP · hard	QF	Fils A.Tirante T.	80 %20 %	Strong favourite	1–0

Rated matches · ordered most one-sided first
Time	Tournament	Round	Match	Probability	Verdict	H2H
00:40	Cincinnati ATP · hard	QF	Fils A.Tirante T.	80 %20 %	Strong favourite	1–0

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
Tour	Correct
ATP / WTA	66 %
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

Thursday, 20 August 2026 · 20 matches

Favourites won

9 / 20

Model expected

12.8

The model expected 12.8 favourites to win; 9 did. See yesterday’s page.

Biggest shock, last 7 days

20 Aug

M25 Slovenj Gradec

ITF · clay

R16

F. Schlossmann beat Kirill Kivattsev

Surprise score

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.