Naomi Osaka vs Elise Mertens Odds & Betting Preview: WTA Western & Southern Open Semifinals

By Stephanie Myles in Tennis
Updated: August 28, 2020 at 5:34 pm EDTPublished:

- After Osaka announced she wouldn’t play Thursday, in solidarity with athletes in other sports, the entire schedule at the Western & Southern Open was pushed back a day
- On Thursday, she confirmed she was still in the tournament and will play Mertens Friday
- Elise Mertens has taken advantage of upsets in her section of the draw, can she pull off an upset on Friday? Read our match preview and best bet below
The first big tournament on the WTA Tour since the shutdown last March played out every bit as unpredictably as you would expect.
The top two seeds went out in their first matches, and No. 3 Serena Williams joined them after an angst-filled defeat Tuesday night to No. 13 seed Maria Sakkari.
Naomi Osaka vs Elise Mertens Odds
Player | Spread | Moneyline at DraftKings | Total |
---|---|---|---|
Naomi Osaka (JPN) | N/A | -159 | N/A |
Elise Mertens (BEL) | N/A | +128 | N/A |
Odds taken Aug. 26
Meanwhile, the state of No. 4 seed Naomi Osaka was unknown.
She had not played since a desultory defeat on red clay to Sara Sorribes Tormo in a Fed Cup qualifier in early February. Osaka won only won three games.
After a hard-fought three-setter over Karolina Muchova of the Czech Republic to open the tournament, she revealed that it was the first time she had played without pain in her right shoulder since last October.

Osaka’s next win was an emphatic one against diminished opponent Dayana Yastremska. The No. 16 seed had twisted her ankle in a marathon victory over Venus Williams and hurt her knee in another three-setter over Bernarda Pera of the US.
Yastremska’s coach, Sascha Bajin, was caught in a spot. He guided Osaka to her back-to-back Grand Slam titles at the US Open in 2018 and the Australian Open in 2019 before being sacked, in his first coaching job at the WTA Tour level.
I always thought that I remain the best player on the court in your eyes, even if I lose.
— Dayana Yastremska (@D_Yastremska) August 26, 2020
Against an in-form Anett Kontaveit in the quarterfinals Wednesday, Osaka once again began slowly. But, again, she found her form and showed her level on a very gusty afternoon.
The semifinals were scheduled for Thursday, however, Osaka chose to withdraw in protest of social justice Wednesday night for the police shooting of Jacob Blake. The entire tournament was postponed until Friday; Osaka confirmed Thursday that she was still in the tournament, and would play.
Naomi Osaka vs Elise Mertens: Head to Head
22 (Oct. 16, 1997) | Age | 24 (Nov. 17, 1995) |
5 | WTA Singles Titles | 5 |
0 | WTA Doubles Titles | 9 |
10 | Ranking | 22 |
5-11 | Height | 5-10 |
No. 1 | Career high ranking | No. 12 |
$14,617,235 | Career Prize Money | $6,293,979 |
1 | Head-to-Head | 1 |
The first meeting between Osaka and Mertens came before Osaka was Osaka.
She was just about to turn 20 and, ranked No. 61.
Still, it took Mertens three sets to beat her.

By the fall of 2019 Mertens had to play Osaka in her hometown of, Osaka. Mertens was outclassed.
Naomi Osaka vs. Elise Mertens – Previous Matches
Tournament | Year | Score | Winner |
---|---|---|---|
Wuhan Open (Wuhan, China) | 2017 | 6-4, 1-6, 6-4 | Mertens |
Pan Pacific Open (Osaka, Japan) | 2019 | 6-4, 6-1 | Osaka |
It will be the fifth match in six days for Mertens with the Thursday break, the fourth in five days for Osaka.
Mertens has had an easier road in singles. But she also played two doubles matches before pulling out of the quarterfinals Thursday.
Naomi Osaka Serving Effectiveness
Opponent | First-serve % | Aces | Break Points Against | Break Points Saved |
---|---|---|---|---|
Karolina Muchova | 47% | 12 | 3 | 2 |
Dayana Yastremska | 54% | 8 | 5 | 5 |
Anett Kontaveit | 55% | 9 | 4 | 1 |
The match may come down to how effective Mertens can be on Osaka’s serve. It’s the best serve she will have faced this week.
Osaka saved just half of the break points she faced on her serve – not a great number given how good her serve is.
Mertens converted on 71 percent of the break-point chances she has had this week – a very impressive stat.
Elise Mertens Effectiveness on Return
Opponent | % of Points Won on Return | Break Points Earned | Break Points Converted |
---|---|---|---|
Rebecca Peterson | 24/40 (60%) | 6 | 5 |
Kristina Mladenovic | 44/95 (46.3%) | 11 | 6 |
Veronika Kudermetova | 28/60 (46.7%) | 6 | 4 |
Jessica Pegula | 23/45 (51.1%) | 5 | 5 |
Osaka the Favorite
Given how slowly Osaka has started her matches you’d have to think Mertens has a legitimate opportunity to pull off at least a set.
Most likely, it would be the first set.
Add in that Osaka’s heart and mind have been elsewhere the last few days (with missing her boyfriend’s birthday, and with her political stand Wednesday), she might take some time to get revved up.
But if Osaka is on a mission and wins that first set, she likely will roll.
Prediction: Osaka in two sets.

Sports Writer
Stephanie gets the straight dope from the tennis insiders. On court, she has represented her country internationally. A BA in journalism led to years on the MLB beat and a decade covering tennis globally. She's written for Postmedia, the Guardian, the New York Times and also publishes OpenCourt.ca.