Tickets sales for the weekend play at next month's Irish Open at Royal Portrush are now close to a sell-out, tournament organisers said on Thursday.
Championship director Antonia Beggs revealed that spectators turning up at the gate on the Saturday and Sunday may have to be turned away.
The organisers' total crowd target for the tournament from Tuesday 26 June to Sunday 1 July is 103,000 spectators.
They are targeting 25,000 on the Saturday and 27,000 on the final day.
Tournament officials are aiming to accommodate 21,000 spectators per day on the Thursday and Friday with significant crowd number also expected on the two practice days.
Earlier this week US PGA winner Keegan Bradley signed up to play in the event at Royal Portrush, meaning three of the four major winners will compete.
The 25-year-old American will participate alongside US Open champion Rory McIlroy and Open winner Darren Clarke.
Italian brothers Edoardo and Francesco Molinari will also play in the 28 June-1 July event.
The participation of the Italian brothers means half of the victorious 2010 European Ryder Cup team will be in the field.
They include former US Open champion Graeme McDowell and three-time major winner Padraig Harrington.
