The French Open’s decision to move the women’s semis away from Roland Garros’s showpiece court is “inappropriate and unfair”, says WTA chief Steve Simon.

With no play possible on Wednesday and more rain forecast on Friday, British number one Johanna Konta’s meeting with Marketa Vondrousova will instead begin at 10:00 BST on Court Simonne Mathieu.

Ashleigh Barty and Amanda Anisimova will meet on Court Suzanne Lenglen.

“They have earned the right to play on the biggest stage,” said Simon.

While the women’s last-four matches, originally scheduled for Thursday, have been switched away from the 15,000-capacity main court to smaller stages, the men’s semi-finals, which see Rafael Nadal play Roger Federer and Novak Djokovic take on Dominic Thiem, will both take place on Court Philippe Chatrier as planned.

“There is no doubt that scheduling has been challenged by weather conditions and the WTA understands the scheduling issues presented at Roland Garros,” added Simon.

“We are, however, extremely disappointed by the scheduling of both women’s semi-finals on outside courts. This decision is unfair and inappropriate.

“We believe other solutions were possible which would have been to the benefit of fans as well as all players.”

• Ruthless Djokovic marches into semi-finals
• Anisimova stuns defending champion Halep
• How Konta has become French Open contender
• What can Federer do to beat ‘King of Clay’ Nadal?

‘Worst-case scenario’ – men’s final on Monday?

Tournament director Guy Forget said further delays could see Saturday’s women’s final moved back to Sunday, with the men’s final switching to Monday.

“It’s not what we hope, but if we have no other choice, then that’s what we will do,” he said.

“When we have uncertain weather, of course; it’s very hard to predict scheduling.

“We have to always study the worst-case scenario, knowing that ideally we want to try to finish on Sunday.”

The newly rebuilt Chatrier, with a capacity of 15,000, is Roland Garros’ main court.

The 10,000-seater Lenglen is the second show court, with the 5,000-seater Mathieu, a semi-sunken court surrounded by four greenhouses, opened this year as the third.

‘Wrong to relegate the women’s matches’

BBC tennis correspondent Russell Fuller at Roland Garros

I understand the need to play the matches early on Friday and that they have got themselves into a situation with selling the tickets for the men’s semi-finals as two separate sessions.

But I still think it is wrong to relegate the women’s matches away from the main courts. How does a young player like Marketa Vondrousova or Amanda Anisimova build a following if they are denied the chance to play on these big courts?

It always seems to be the women who suffer in these situations.

I suspect that there is some small print on the tickets as well that says that the organisers cannot guarantee any particular matches in the case of bad weather.

They could have used that disclaimer to create space for the women on Philippe Chatrier.

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World number one Novak Djokovic reached his first French Open semi-final since 2016 with a clinical win over German fifth seed Alexander Zverev.

The 32-year-old Serb, chasing his fourth straight Grand Slam, won 7-5 6-2 6-2 in their rain-delayed quarter-final.

Zverev, 22, failed to serve out the first set and it proved pivotal as Djokovic dominated from then on.

The 15-time Grand Slam champion will play Dominic Thiem in the last four.

Austrian fourth seed Thiem, last year’s beaten finalist, secured his place in the semi-finals with a 6-2 6-4 6-2 win over Russian 10th seed Karen Khachanov.

Djokovic and Thiem are set to meet at about 15:00 BST on Friday, following the other, highly anticipated semi-final between Spain’s defending champion Rafael Nadal and returning Swiss great Roger Federer.

Remarkably, it is the first time at a Grand Slam since the French Open in 2012 that Djokovic, Federer and Nadal have all made it through to the semi-finals.

“We have still been enjoying some of our best tennis in biggest events. That’s great to see,” Djokovic said.

“Nadal and Federer are arguably the biggest legends of this sport and most successful players ever, so to be in the mix with them and have a successful career myself is quite a great feeling.”

However, Friday’s play is expected to be disrupted by heavy rain in Paris, a forecast which has led to a reshuffle of the schedule.

With both men’s matches on Court Philippe Chatrier, British number one Johanna Konta’s semi-final has been moved to the 5,000-capacity Court Simonne Mathieu.

• What can Federer do to beat ‘King of Clay’ Nadal?
• How has Konta become French Open contender?
• American teenager Anisimova stuns champion Halep
• Rearranged schedule for Friday’s semi-finals – is it fair?

‘History-making on Djokovic’s mind’

After winning the Wimbledon, US Open and Australian Open titles, Djokovic is aiming to hold all four majors at the same time – for the second time in his career – by triumphing at Roland Garros.

Djokovic previously achieved the feat when he claimed his maiden title on the Paris clay in 2016, which saw him become only the second man after Australian great Rod Laver to hold all four Slams simultaneously in the Open era.

But 12 months ago, after form and fitness problems, the possibility of Djokovic putting himself in this position again seemed unlikely.

Now he is only two more wins away from another piece of history after cruising into the last four in Paris without dropping a set.

“The presence of history-making is stronger than ever right now in my career,” said Djokovic.

“I think the longer I play or the further I go in my career, the sense of history-making is only getting stronger.

“That’s one of the greatest motivations I have.”

After losing serve for a 5-4 deficit in the first set, Djokovic suddenly raised his game to another level as Zverev was left suffocated by his relentless returning and court craft.

Three straight games swung the opener in the Serb’s favour and he continued to wear down Zverev in the next two sets, pinning him deep in baseline rallies as well as stretching him with some deft drop-shots and lobs.

‘Once he’s in control, he’s very tough to beat’

Zverev, aiming to reach his first Grand Slam semi-final, did not help himself by buckling under pressure at crucial times.

After failing to serve out the first set, a double fault on set point handed it over and, to gasps from the Chatrier crowd, he did the same on set point in the second – after already producing three others in the same game.

The pressure continued to tell as the German chased the match in the third.

Zverev handed another break point to Djokovic by lumping a backhand drive volley over the baseline, then stiffed a routine volley into the net as the Serb took a 4-2 advantage.

With defeat looming, Zverev managed to save one match point with an ace, but Djokovic clinched victory with his second by wearing his opponent down in a rally and forcing the error as a sliced backhand went long.

Zverev’s victory against Djokovic in the ATP Finals in November seemed to indicate a Slam breakthrough could be around the corner.

Yet, when it mattered in the five-set format, Djokovic proved he is still the man to beat.

“I really thought the first set should have gone my way,” said Zverev. “And then I played three really bad games from there on.

“Once he’s in control, he’s very tough to beat.

“When he gets up on you, he doesn’t let go. When he’s up in the score, he’s unplayable.”

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Britain’s Alfie Hewett advanced to the wheelchair singles semi-finals with a 6-2 7-6 (7-4) win over France’s Stephane Houdet.

The 21-year-old, who lifted the title in 2017, wrapped up the first set with a third break of Houdet’s serve, but was made to work harder for the second.

Fellow Briton Gordon Reid is also in the last four after battling past Belgium’s Joachim Gerard 3-6 6-4 6-3.

The 27-year-old will play Japanese top seed Shingo Kunieda next.

Hewitt will take on Argentine defending champion Gustavo Fernandez, who he beat in the 2017 final, in the other side of the draw.

“Shingo is number one in the world right now, and he’s back to what I would say is his best form,” said former Australian Open and Wimbledon champion Reid of his prospects of his next opponent.

“He’s always a tough opponent to play against, but I know I can beat him – I’ve beaten him in the past, and I’ve got the game to beat him. I’ll go away, prepare, and try and do that tomorrow.”

• Reid confident ahead of Roland Garros
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Hewitt and Reid will also team up in the doubles on Friday, when they face Fernandez and Kunieda once more in their opening match.

Whether it is trusting her ability more on the clay court, or excitedly talking about her pet dog Bono in chats with journalists, Johanna Konta has cut a more content figure at the French Open this year.

It is perhaps obvious when she has become the first British woman since Jo Durie in 1983 to reach the semi-finals at Roland Garros.

Nevertheless it is a stark contrast to 12 months ago when she suffered her fourth straight first-round exit on the Paris clay.

Then, Konta was ponderous and erratic on the red dirt, going on to criticise the British media for “not making things easy” when journalists mentioned her poor record at Roland Garros.

After a remarkable run to this year’s last four – where she plays Czech teenager Marketa Vondrousova at 10:00 BST on Friday – her previous troubles here have been consigned to history.

“She looks like a different sort of player – more rounded, physically and mentally,” Sue Barker, the last Briton to win Roland Garros in 1976, told BBC Sport.

So how exactly has Konta, the 26th seed, transformed herself into a contender for the title?

• Schedule for Friday’s semi-finals
• Konta playing better than anybody – Barker

‘She could always play on the clay, but didn’t have the belief’

Heading into the European clay-court swing Konta was ranked 45th in the world and had never won a main-draw match at Roland Garros.

But her newly-found confidence on the surface quickly became apparent as she reached WTA finals at the Morocco Open and Italian Open.

Despite both finals ending in defeats, Konta had proved she had the ability to cause problems for higher-ranked opponents on a previously tricky surface.

Konta insists she has always retained belief she could succeed on clay and says her work with coach Dimitri Zavialoff, who she linked up with last October, is not specific to the red dirt but aimed at “crossing over to all surfaces”.

“To have never won a match in the French Open and find yourself in the semi-final, it shows it is all in the mind,” Barker said.

“She could play on clay, she just never believed in herself. Now she does.”

Durie, a former world number five, added: “You have to come to terms mentally and emotionally with the surface before you tweak your game a little bit.

“For Jo in particular, she has an aggressive game, it was just a matter of being able to slide a little bit better and keep the balance.”

How Konta has worked out how to succeed on clay is starkly illustrated by the stats:

• Nobody has won more tour-level matches than Konta on the surface this year

• Konta’s record on the clay is 15 wins and three defeats in 2019

• Only Croatian Petra Martic, who lost to Vondrousova in the quarter-finals, has matched her tally of victories

• Konta had only earned seven tour-level victories on clay, losing 15 matches, in her whole career before this year

‘Tactically she is thinking very well – and not panicking’

Konta’s service game and hard hitting have always been her strengths, but in the aftermath of her 2017 Wimbledon success – where she reached the last four – those weapons went awry.

Now she has rediscovered her firepower to devastating effect:

• Konta has won 75.8% of her service games in 2019, nobody outside the world’s top 10 – having played more than 11 matches – has won more

• She has won 82% of her service games (40 from 49) at Roland Garros, with only two players having a higher percentage

• The Briton has won 70% of her first serve points at Roland Garros (150 from 213), a tally only bettered by Ekaterina Alexandrova (74%), Serena Williams (74%), Ashleigh Barty (72%) and Madison Keys (71%) from those who have played more than two matches.

In her stunning quarter-final win over American seventh seed Sloane Stephens, Konta cantered towards victory by winning 18 straight service points at the start of the second set.

“I like the way she has tweaked her serve a bit so that she is hitting those higher bouncing serves,” Durie said.

“She has more cover on the ball on the forehand, she’s hitting some great cross-courts and she’s really brought in the drop-shot when she has her opponent behind the baseline.

“So, tactically she is thinking very well.”

Konta’s belief in her service game, and ability to remain calm, is also shown by the fact no player inside the top 100 has saved as many break points as the Briton this year.

That resilience proved key for Konta, who has saved 64.4% of break points, when she fought off a chance for Stephens in the first game of their quarter-final to hold.

“She is not panicking out there,” British Fed Cup captain Keothavong added.

Autonomy and trust instilled by new coach

Linking up with France-born coach Zavialoff, who enjoyed success with Swiss pair Stan Wawrinka and Timea Bacsinszky, has proved to be the spark in reigniting former world number four Konta’s career.

Zavialoff’s approach is giving more “autonomy” to the player, enabling Konta to trust herself to – in her words – “problem solve” better on court.

“He’s been great in just encouraging me and inviting me and giving me the space to play the way I want to play and not putting too many restraints or restrictions on myself,” Konta said.

“I’m enjoying that self-discovery process of being the player who I want to be and trusting the decisions I make out there.

“That’s been a really nice journey to be on and continue to be on, because it makes what I do out there very self-satisfying.

“I feel a lot of ownership over it, which is a really nice place to be.”

Anne Keothavong, who guided Konta and her team-mates to promotion to the Fed Cup World Group II stage earlier this year, believes Konta is reaping the rewards of being settled in both her tennis and personal life.

“She is enjoying her tennis a lot more, she is happy off the court and that reflects in her tennis she is able to produce on a match day,” said Keothavong.

“There is better clarity when she walks on the court, what she wants to do, how she needs to win the match.

“She plays to her strengths. She has always been capable of doing different things but now does it with more confidence.”

‘Self-assured’ Konta always maintained belief

Konta, of course, has already proved she has the ability to mix it with the world’s best players.

Her breakthrough run came at the 2016 Australian Open where she lost to Germany’s Angelique Kerber in the semi-finals, before she became the first British woman to reach the Wimbledon last four since 1978 the following year.

That run at SW19 propelled her to fourth in the world rankings, yet the effects of increased scrutiny on a home player succeeding at Wimbledon appeared to hamper her as she won just two more matches in 2017.

“She said she felt like she came up against a brick wall, all those emotions, she just found it hard to get going,” Durie said.

“For a little while she was trying to cope with success, that can happen.”

Hiring American coach Michael Joyce for the 2018 season proved unsuccessful, winning only two Grand Slam matches and her ranking dropping from ninth in the world to the cusp of the top 50.

After ending that partnership, Konta hired Zavialoff after a trial run and the decision has proved inspired.

Unpredictable women’s tournament wide open

Konta’s path to the latter stages – and a potential chance to become the first Briton to win the Roland Garros title since Barker in 1976 – has opened up following an unpredictable women’s tournament.

World number one Naomi Osaka, second seed Karolina Pliskova and former champion Serena Williams all lost in the third round and only three top-10 seeded players reached the women’s quarter-finals.

American teenager Amanda Anisimova stunned 2018 champion Simona Halep in straight sets and Australian eighth seed Ashleigh Barty knocked out Madison Keys to set up an unfamiliar-looking last-four line-up.

Halep’s defeat means there is guaranteed to be a first-time Grand slam champion come Saturday, with Konta the only one of the remaining quartet who has ever reached a singles semi-final before but Barty is the highest-ranked player.