The Professional Darts Corporation is still awaiting Government guidance over Covid certification just five days before it prepares to welcome a capacity crowd to the World Matchplay at Blackpool's Winter Gardens.
The tournament starts on Saturday but the venue layout will be redesigned after Sunday night's action in order to admit almost 2,000 spectators per session from Monday onwards when legal restrictions on Covid are lifted, with the event running until July 25.
The PDC had previously said there would be no requirement for spectators to provide proof of full vaccination, a recent negative test or immunity in order to gain entry, after the Government said on July 5 that Covid certification would not be mandatory.
While legal restrictions on Covid are being lifted from Monday, guidance will make clear that people and firms are expected to continue to take action to limit the spread of the virus.
Speaking on Monday, Prime Minister Boris Johnson said: "As a matter of social responsibility we're urging nightclubs and other venues with large crowds to make use of the NHS Covid pass, which shows proof of vaccination, a recent negative test or natural immunity as a means of entry."
The PDC is now understood to be seeking urgent guidance from the Department of Digital, Culture, Media and Sport (DCMS) on the issue, but still plans to press ahead with capacity crowds.
EFL chief executive Trevor Birch said on Monday that his organisation would liaise with the Government in the days ahead for further clarity on the matter.
Covid certification has been used throughout the second and third phase of the Government's Events Research Programme from last month onwards, which has included England's matches at Euro 2020, Wimbledon and this weekend's British Grand Prix at Silverstone.
The PDC's head of media Dave Allen told the PA news agency last week that the World Matchplay would look and feel "in many ways like 2019".
Allen also said last week that any advice on face coverings would be followed, but that "at present we do not expect fans will need to wear a mask within the venue".
A Downing Street spokesperson said on Monday the Government would "expect and recommend" people in England to wear face masks in crowded areas, such as on public transport.