French Open Thursday Semi-final Tips: Swiatek's odds too big to ignore

• Swiatek a proven commodity at Roland Garros 

• Bet builder suggestions for Swiatek v Sabalenka

• Can massive outsider Boisson do it?

Before a ball was hit this tournament you would have had short odds on Aryna Sabalenka, Iga Swiatek, Coco Gauff and Mirra Andreeva as the final four players.

It had been a tournament without many notable upsets. That was until the sensation of the tournament Lois Boission, playing her first ever Grand Slam main draw, proved to be a banana skin by upsetting Andreeva who I stated was far too short at 1.121/8 to win.

Last week I pointed out that Boisson would be worth some coffee money to win the tournament, and from 650.0649/1 in the Betfair Exchange's French Open winner market she is now settling around 32.031/1, and not without a chance of reaching the final.

However, before Boisson burst on the scene it was Aryna Sabalenka who I thought was a justifiable favourite to win this French Open. The world number one starts as favourite to defeat Iga Swiatek, and although there is reason in that price it is so difficult to ignore the four time champion's record.

Swiatek odds too big to ignore 

After a chaotic 12 months four-time Roland Garros champion Iga Swiatek has been overtaken atop the most credible ELO rankings by Aryna Sabalenka, which I trust as a faithful measure of player quality.

Swiatek has demonstrated her clay court prowess this tournament and slow conditions are to her liking, but there is an ever lingering doubt that it could all combust at any moment as has been the case routinely throughout 2025.

If a player can hang with Iga long enough, it is possible to get under her skin, and she can completely unravel.

Swiatek came close to defeat against Elena Rybakina, who was hitting the Pole off the court for 45 minutes, before the Kazakhstani ran out of steam and her nerves came to the fore at unfortunate times.

Even though Swiatek tilted that contest in her favour, there was an air of inevitability about that outcome as Rybakina became a deer in the headlights and has never had high expectations on the clay.

The demons are still there for Iga, and Sabalenka is the ultimate test of Swiatek's current standing in the sport.

Swiatek comfortably leads their clay court encounters four wins to one, and you only need to look at her collection of Suzanne Lenglen trophies to know about her best level in this environment.

Yet, I still understand Sabalenka's favouritism. The Belarusian is constantly improving and evolving her game, and it was evident how many strings she has to her bow in a commanding defeat of Olympic champion Qinwen Zheng.

It was a highly impressive dismantling of an elite clay courter, and an exhibition of the tools Sabalenka possesses to rattle Swiatek's rhythm.

That said, is it reasonable that Swiatek is the outsider to win this match? The Pole has a near perfect record in Paris and a slow court is too her benefit for this particular match-up.

As volatile as Swiatek has been of late, she has looked in better shape this tournament and will surely believe in her own superiority over Sabalenka.

At 2.1411/10 proven commodity Swiatek is simply too big.

Bet builder ideas

Throughout this fortnight Betfair has been running a bet builder promotion where Betfair punters can receive a free bet if they place a bet builder of £5 or more.

Swiatek and Sabalenka have met plenty of times and it might be worth considering some of these trends in bet builder selections.

All four of Swiatek's victories over Sabalenka on clay have been achieved in straight sets, and by an average of a 7.25 game margin. If you believe in a Swiatek win then the evidence points to two sets and under games lines.

If you have faith in Sabalenka, all but one of her victories over Swiatek have been achieved in three sets meaning overs lines and a 2-1 set victory are your friends.

Boisson the toast of Paris

Undoubtedly the best story of this French Open is the breakthrough emergence of Lois Boisson.

Before this tournament I was only aware of the French player because of an unfortunate incident in a match with Harriet Dart that went viral on the internet due to the Brit suggesting 'she smells really bad'.

The Dijon native has shown the past two weeks that it is not only her city's mustard that can cause a stink, but also her hugely impressive clay court tennis.

Boisson has claimed the scalps of three seeds this tournament - Elise Mertens, Jessica Pegula and most recently Mirra Andreeva.

Her performances against both Pegula and Andreeva were exceptional, and earned through the power and variety of her fearsome forehand.

She has the crowd on her side, and made very good use of the pressure cooker atmosphere that the Parisian public generated in her defeat of Andreeva, who was clearly affected by the intensity of the crowd.

Boisson did a good job of bullying Andreeva's forehand wing and she will surely employ a similar strategy against Coco Gauff who is well known to have serious issues protecting that wing.

Gauff may have defeated Madison Keys in the quarter-final, but by all accounts it was a messy performance. Gauff was able to coax enough errors out of Keys overall, but the Australian Open champion will feel she let a good opportunity slip away.

There are obvious vulnerabilities in the Gauff game, and it is not impossible for Boisson to back up her Andreeva success. At 5.14/1 on the Betfair Exchange I have seen much worse bets. 

Gauff may win this, but don't discount Boisson to continue being the toast of Paris.

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