BrazilWTA Sao PauloFinished

Predictions graded

Mary Stoiana #127United States2Claire Liu #116United States0

Sets 6-3 · 7-5Wed 16 Sept 2026, 15:50 Predictions gradedFirst RoundHard

Predictions2–433%

Edges0–20%

Player Profiles

Ranking advantageClaire Liu · 11 places

Mary Stoiana

United States

Limited reliable public profile information was found. Use the structured ranking and form data as the main current context.

Current ranking: #127
Peak ranking: —
Current age: 23
Preferred surface: —
Hand: —
Height: —

Claire Liu

United States

American right-hander born 25 May 2000. Her documented singles career high is No. 52; official WTA ranking history shows a substantial 2026 rise from outside the top 200 earlier in the season.

Current ranking: #116
Peak ranking: #52
Current age: 26
Preferred surface: —
Hand: Right handed
Height: 170 cm

Quick Take

Pre-match view

Context last updated 13 Sep 2026, 15:47 · Europe/Bucharest

Claire Liu's strong recent form and hard-court success give her the edge over Mary Stoiana.

Liu is favored to win the match and the first set, with value on both bets. The match could be competitive, but Liu's momentum is the key factor.

Context

Liu, 26, is a right-hander ranked 111 and has won 17 clay and 12 hard matches in 2026.
Her current run includes wins over Blinkova, Jeanjean, and Quevedo, all ranked between 95 and 127, showing she can beat players near Stoiana's level. Stoiana's last match was a three-set loss to Riera, but she had won three of her previous four, so the form gap is real but not extreme.
- Liu's last five hard-court matches: W vs Blinkova (95), W vs Jeanjean (127), W vs Quevedo (107), W vs Lepchenko (181), W vs You (206).
- Stoiana's last match: L vs Riera (147) 4-6 7-6(7) 6-3 on hard.
Stoiana, 23, is ranked 122 and has a 64.7% first-serve points won rate in her last 15 matches.
Her second serve is a weak point, and Liu's hard-court return numbers are strong enough to attack it. If Stoiana falls behind in rallies, Liu can extend points and force errors, especially given Stoiana's 4.0 double faults per match.
- Stoiana last 15 overall: second-serve points won 45%, double faults per match 4.0.
- Liu last 15 on hard: return points won 47.2%.

BetBugs edges

Compare BetBugs' chances with the market's.

BetBugs probabilities

How likely BetBugs thought each outcome was.

Result0 of 1 landed

Signal quality Medium · Uncertainty band Lean · Market price 1.73
The read
Liu's superior recent form and hard-court record give her the edge in this Bo3 match.
- Claire Liu last 15 overall record 10-5 (66.7%), Mary Stoiana 8-7 (53.3%)
- Liu on hard last 15: 6-2 (75%), Stoiana on hard last 15: 8-6 (57.1%)
- Liu has won 5 straight matches in this tournament, Stoiana lost her last match
BetBugs · Match WinnerlostClaire LiuEstimated chance62%

Games2 of 2 landed

Signal quality Low · Uncertainty band Slight lean · Not priced
The read
Competitive matchup with both capable of extending sets suggests a higher total games count.
- Stoiana's last 15 matches average 23.8 games per match
- Liu's last 15 matches average 21.2 games per match
- Both players have had multiple three-set matches recently
BetBugs · Total GameswonOver 21.5Estimated chance55%
Signal quality Low · Uncertainty band Slight lean · Not priced
The read
First sets have often been competitive, with several going to 10+ games.
- Stoiana's last 5 first sets: 6-4, 6-3, 1-6, 6-3, 6-7
- Liu's last 5 first sets: 6-0, 6-2, 7-5, 6-3, 7-5
- Both players have had close first sets in recent matches
BetBugs · Set 1 Total GameswonOver 9.5Estimated chance52%

Sets0 of 1 landed

Signal quality Medium · Uncertainty band Lean · Market price 1.73
The read
Liu's strong recent starts and momentum favor her taking the opening set.
- Liu has won the first set in 4 of her last 5 matches
- Stoiana lost the first set in her last match and in 3 of her last 5
- Liu's first set win conversion career 85%, Stoiana 84%
BetBugs · Set 1 WinnerlostClaire LiuEstimated chance60%

Match stats0 of 0 landed

Signal quality Low · Uncertainty band Near coin-flip · Not priced
The read
Both players have moderate double fault rates, making over 6.5 likely.
- Stoiana averages 4.0 double faults per match overall, 3.9 on hard
- Liu averages 3.1 double faults per match overall, 3.6 on hard
- Combined average double faults per match on hard: ~7.5
BetBugs · Total Double Faultsnot gradableOver 6.5Estimated chance50%

Prediction history

Claire Liu has been highly reliable when projected to win

Claire Liu has fulfilled 8 of 8 predictions when projected to win. The average estimated probability was 63.9%, with an expected 5.1 fulfilled predictions, indicating strong overperformance. All eight matches resulted in wins, with no losses or draws.

Recent evidence for Claire Liu8 matches

Date / competitionMatch resultPredictedActualResult

13 Jul·WTA Iasi

#146Claire Liu2-0#370Ipek Oz

BetBugsClaire Liu to win·72%

13 Jul 2026

WTA Iasi

#146Claire Liu2-0#370Ipek Oz

Claire Liu to win

72%probability

Claire Liu won

12 Jul·WTA Iasi

#146Claire Liu2-0#461Maria Sara Popa

BetBugsClaire Liu to win·82%

12 Jul 2026

WTA Iasi

#146Claire Liu2-0#461Maria Sara Popa

Claire Liu to win

82%probability

Claire Liu won

29 Jun·WTA Wimbledon

#145Claire Liu2-1#100Hanne Vandewinkel

BetBugsClaire Liu to win·62%

29 Jun 2026

WTA Wimbledon

#145Claire Liu2-1#100Hanne Vandewinkel

Claire Liu to win

62%probability

Claire Liu won

25 Jun·WTA Wimbledon

#145Claire Liu2-1#206Elena Pridankina

BetBugsClaire Liu to win·62%

25 Jun 2026

WTA Wimbledon

#145Claire Liu2-1#206Elena Pridankina

Claire Liu to win

62%probability

Claire Liu won

23 Jun·WTA Wimbledon

#169Despina Papamichail0-2#145Claire Liu

BetBugsClaire Liu to win·62%

23 Jun 2026

WTA Wimbledon

#169Despina Papamichail0-2#145Claire Liu

Claire Liu to win

62%probability

Claire Liu won

Previous match context available

Mary Stoiana

8W 7L

4-6 7-6(7) 6-3#147Julia Riera

6-3 6-2#158Jazmin Ortenzi

6-1 6-2#18Alexandra Eala

6-3 4-6 6-4#138Yue Yuan

6-7(5) 6-3 6-3#207Katie Swan

6-4 6-3#216Harmony Tan

6-2 7-6(4)#50Tereza Valentova

6-0 5-7 6-4#93Oksana Selekhmeteva

6-2 7-6(3)#106Veronika Erjavec

2-6 6-4 6-3#69Alina Korneeva

6-7(5) 6-0 6-4#55Peyton Stearns

6-4 2-6 6-2#179Yeon Woo Ku

6-3 6-4#288Julieta Pareja

6-1 6-1#330Anna Sinclair Rogers

3-6 6-2 7-5#94Mananchaya Sawangkaew

Claire Liu

10W 5L

6-0 2-6 7-5#95Anna Blinkova 6-2 6-4#127Leolia Jeanjean

7-5 6-1#107Kaitlin Quevedo

6-3 6-3#181Varvara Lepchenko

7-5 6-0#206Xiaodi You

4-6 6-2 6-4#446Heather Watson

6-4 6-3#90Sinja Kraus

6-4 6-2#160Polina Iatcenko

7-5 6-2#84Yulia Putintseva

6-4 6-1#406Ipek Oz

6-3 6-4#399Maria Sara Popa

7-5 6-0#90Sinja Kraus

6-3 6-7(5) 6-2#4Cori Gauff

7-5 6-3#53Zeynep Sonmez

4-6 6-3 6-4#81Hanne Vandewinkel

Stat Battle

Last 15 match performance, compared side by side.

MSMary StoianaStoiana

Last 15

0–5

9 core stats · 4 even

Claire LiuLiuCL

Claire Liu carries the stronger recent form — Mary Stoiana's route runs through return pts won.

Serve · 0–4 · 1 even

1st Serve In62.4%+1.4pp63.8%

1st Serve Won64.7%—65.3%

2nd Serve Won45.0%+4.2pp49.2%

Aces / Match1.9+0.92.8

Double Faults / Match4.00.9 fewer3.1

Return · 0–0 · 1 even

Return Pts Won44.6%—44.8%

Pressure · 0–0 · 2 even

Break Pts Converted46.9%—47.1%

Break Pts Saved56.5%—56.1%

Points · 0–1

Total Pts Won51.0%+1.2pp52.2%

Serve · 0–4 · 1 even

62.4%1st Serve In+1.4pp63.8%

64.7%1st Serve Won—65.3%

45.0%2nd Serve Won+4.2pp49.2%

1.9Aces / Match+0.92.8

4.0Double Faults / Match0.9 fewer3.1

Return · 0–0 · 1 even

44.6%Return Pts Won—44.8%

Pressure · 0–0 · 2 even

46.9%Break Pts Converted—47.1%

56.5%Break Pts Saved—56.1%

Points · 0–1

51.0%Total Pts Won+1.2pp52.2%