England captain Leah Williamson is set to miss this summer's Women's World Cup after suffering a ruptured ACL in Arsenal's defeat at Man Utd on Wednesday.
Williamson was taken off after collapsing to the ground only 12 minutes into Arsenal's 1-0 loss at Leigh Sports Village, with her knee appearing to be the source of her discomfort.
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A stretcher was called for and while the 26-year-old was able to walk off the pitch, aided by two Arsenal physios, a scan has shown her to have suffered a ruptured anterior cruciate ligament, which normally takes at least six months to recover from.
That will mean she will most likely be unable to lead the Lionesses at the Women's World Cup in Australia and New Zealand, which runs from July 20 to August 20. Sarina Wiegman names her squad in late May and England's opening game is against Haiti on Saturday 22nd July in Brisbane.
Less than two weeks prior to suffering the injury injury, she led England to the inaugural Finalissima trophy at Wembley, beating Brazil in a penalty shoot-out to land the second piece of silverware since Wiegman named her as captain ahead of last summer's Euros.
Arsenal manager Jonas Eidevall initially blamed the Man Utd pitch for Wednesday's incident and said he was unsure how long Williamson would be unavailable for, but in confirming the severity of her injury on Friday Arsenal have announced she will undergo surgery in 'due course'.
"Everyone at Arsenal will be supporting Leah closely throughout the journey ahead and we would ask that her privacy is respected at this time," the club said in a statement.
It is a major blow for England, who will also be without Williamson's injured Arsenal team-mate Beth Mead - top scorer and player of the tournament at Euro 2022 - for the World Cup.
England boss Wiegman said in March, when naming her most-recent squad, Mead was unlikely to recover from her ACL injury in time to make her World Cup squad.
Well-wishes have already begun to come in from around the WSL, with Man City boss Gareth Taylor telling his pre-match press conference: "It's not good for Leah or Arsenal or England. Best wishes go to Leah, it'll be a tough moment for her, especially at this stage of the season."
Analysis: Another hammer blow for Arsenal and England
Sky Sports' Charlotte Marsh:
"If you're an Arsenal and England fan, the hits just keep on coming. The spectre of the ACL injury has reared its ugly head once again, taking down another big gun in Williamson.
"Let's start with the Gunners. Their grip on the title race is quickly slipping away.
"Not only have they been without their two key forwards in Mead and Vivianne Miedema - who were injured within a week of one another - for much of the season, they also recently had their captain, Kim Little, ruled out for the remainder of the campaign.
"Now, four days after Little's injury was announced, Williamson is also expected to be sidelined for much of the calendar year, let alone the season.
"The announcement also comes 48 hours ahead of Arsenal's Champions League semi-final first leg in Wolfsburg. Already a daunting task at the five-time finalists - who knocked them out in the quarter-finals last year - it will truly be a test of the Gunners' squad depth and resilience.
"England will be without their captain heading into a World Cup, in which they are one the favourites. Now, they have to try and win without two of their pillars last summer in Williamson and Mead.
"Sarina Wiegman has already ruled Mead out of contention and Williamson's centre-back partner, Millie Bright, has also struggled with injury in recent weeks, although is still expected to make the squad. Wiegman arguably had too many options for her Euro 2022-winning team, but now faces the task of piecing together a new XI.
"Could this too open the door again for Steph Houghton at international level? The Man City captain has spoken of her disappointment on missing out on England's squad last summer after returning from her own injury, and would be a reliable deputy for Williamson as both a player and a leader.
"But above all of this, it shows that without question, the women's game needs urgent and in-depth research into the impact of ACL injuries on players. This is not just a WSL or European issue - it is a global problem that needs addressing and correcting.
"The women's game is growing at an exponential rate, but research into the issues facing female athletes often remains behind the curve. It is the players who bear the brunt of these potentially career-ending injuries and more must be done to protect them."
Why are ACL injuries so common in women's football?
Female footballers are up to six times more likely to suffer an ACL injury than their male counterparts, and Inside the WSL sat down with players, physios and doctors to try and find out why.
Unfortunately, it's not an uncommon sight to see a women's club announce a player will be sidelined with a ruptured ACL.
The issue also came to the fore during the summer's European Championships. Ballon d'Or winner Alexia Putellas missed the tournament after rupturing her ACL just days before Spain's opening game. Simone Magill also picked up the same injury in Northern Ireland's opening game of the tournament against Norway, just days after signing for Aston Villa.
France striker Marie-Antoinette Katoto also limped off in their second group game against Belgium, having also ruptured her ACL. She had been one of the favourites to win the Euro 2022 Golden Boot.
You could keep reeling off the names of female players who have gone through the long process of ACL rehabilitation, but as yet, very little scientific research has been done into why women are more likely to suffer from the injury than men.