The stadium in Falmer is the home of Brighton and Hove Albion football team.
But matches are being swapped for swabs as the appointment-only centre has been converted into a drive-thru testing facility.
Testing is strictly by appointment only, and those experiencing symptoms of the virus must follow the government and NHS advice.
The site is part of the government’s UK-wide drive to increase testing for thousands more NHS staff and other key workers. The facility will be piloted for its first few days of operation.
Brighton and Hove Albion chief executive Paul Barber said: “It is hugely impressive, and a great triumph of both teamwork and hard work. The Amex will be the biggest testing site anywhere on the south coast, and will be used for self-testing and assisted testing.
“The centre was scheduled to see more than 50 NHS frontline workers on Saturday afternoon, and they will have the results of their tests within 48 hours. Within a few days, the site should reach its capacity of up to 1,000 tests a day.
“The members of our club and Sodexo staff who will be on site day to day have all been trained; and the level of attention detail is phenomenal. And, having visited the site today, the team spirit was truly humbling.
“Huge credit must go to our safety and security team, led by Ade Morris, the Sodexo team led by Andy Perkins and Sophie Partridge and her team at Deloitte; they have been patient, diligent and supportive to the DHSC, NHS England and various other sub-contractors to make this happen.”
The Amex launch is part of the government’s partnership with universities, research institutes and companies to begin rollout of the network of new labs and field testing sites across the UK, with 32 testing sites opened to date.
The network of sites will provide thousands more PCR swab tests – which are used to identify if you currently have the virus – for critical key workers, starting with NHS front line staff. It means those who test negative for coronavirus can return to work as soon as possible, and those who test positive are able to recover.
Adam Doyle, who is leading Sussex NHS’s coronavirus fight, said: “Testing more of our staff and other key workers, so those who are fit can return to work, is an important part of our plans for responding to the virus.
“This is one of four drive-through testing sites we now have across Sussex, supported with vehicles to test staff at home if they are unable to travel.
“I’d like to thank colleagues from across the NHS, local councils and of course Brighton & Hove Albion Football Club for all their hard work in getting all these testing facilities up and running.”
The Amex is already being used for storage of vital NHS supplies and, together with the club’s training centre at Lancing, will be available for NHS training and local emergency services, in order to coordinate their efforts in the fight against the virus.
The stadium has also been offered to the local authority as a field hospital, if needed, but it said this would only be likely in a very extreme situation, with other venues in the city more suited to be used in this manner.
The club delivered supplies initially designated for the Arsenal and Manchester United matches to staff at the Royal Sussex Hospital.
It has also committed 1,000 match tickets for NHS staff once the pandemic is over and it is safe for fans to return to watch football.