A campaign group has been given the green light to take its legal battle over plans to almost triple the size of the Wimbledon tennis site to the Court of Appeal.
In July, Mr Justice Saini dismissed Save Wimbledon Park's (SWP) High Court legal action against the Greater London Authority (GLA) over its 2024 decision to grant planning permission for the expansion.
The proposals, submitted by the All England Club, would see the construction of 38 new tennis courts and an 8,000-seat stadium on the grounds of the former Wimbledon Park Golf Club, allowing it to host Wimbledon qualifiers.
On Wednesday, SWP said the Court of Appeal had granted it permission to appeal.
In a court order dated November 13, Lord Justice Holgate said: "The grounds of appeal are arguable with a real prospect of success.
"The case law on scheme benefits, deliverability, relevance, material considerations and irrationality merits review by the Court of Appeal."
A spokesman for SWP said: "We are delighted with the grant of permission.
"There are a number of important flaws in the planning decisions which need to be resolved and we hope to be able to press ahead quickly with the appeal."
A date for the appeal hearing, which is set to be held over two days, is yet to be confirmed.
The expansion proposals would see seven maintenance buildings, access points and an area of parkland with permissive public access constructed, in addition to the courts and associated infrastructure.
They would also include work on Wimbledon Lake.
After Merton Council approved the plans, but Wandsworth Council rejected them, the Mayor of London's office took charge of the application, but Mayor Sir Sadiq Khan recused himself from the process after previously expressing support for the development.
Planning permission for the scheme was granted by Jules Pipe, London's deputy mayor for planning, who said the proposals "would facilitate very significant benefits" which "clearly outweigh the harm".
Barristers for SWP told the High Court at a two-day hearing in early July that the decision to approve the plans was "irrational" and should be quashed.
They claimed that Wimbledon Park - a Grade II*-listed heritage site partly designed by Lancelot "Capability" Brown - was covered by trusts and covenants governing how it could be used.
The GLA and the All England Club defended the challenge, with the court told that the restrictions were not "material".
In a ruling, Mr Justice Saini found that the decision to approve the plans was "a planning judgment rationally exercised and having regard to appropriate and relevant factors".
SWP said following the ruling that it believed Mr Justice Saini "took insufficient account of the statutory trust and the restrictive covenants".
Separate High Court proceedings are ongoing over whether a statutory trust existed, with a hearing in that case due to take place in January 2026.
A GLA spokesperson said: "The Mayor believes this scheme will bring a significant range of benefits including environmental, economic, social and cultural benefits to the local area, the wider capital and the UK economy.
"It will create new jobs, public green spaces and cement Wimbledon's reputation as the greatest tennis competition in the world.
"With legal proceedings ongoing, it is inappropriate to comment further at this stage."
A spokesperson for the All England Club said: "Following the High Court's dismissal on all grounds of the recent judicial review, we are confident that the Court of Appeal will ultimately judge that the High Court made the correct decision in upholding the GLA's grant of planning permission for a development that will enable us to deliver one of the greatest sporting transformations since the 2012 Olympic and Paralympic Games.
"Our plans will create a permanent home for the Wimbledon Qualifying Competition but crucially they also deliver 27 acres of beautiful new parkland for local people to enjoy, providing the public access to green space that has been used as a private members' golf club for more than 100 years.
"We have spoken to more than 10,000 people who have taken the time to come in person and understand our plans in detail. The vast majority of people just want us to get on and deliver the many benefits on offer as soon as possible."
