The Tyrone v Kerry All-Ireland football semi-final has been postponed due to an outbreak of Covid-19 in the Tyrone camp.
The two teams had been due to meet at Croke Park on Sunday August 15 but the game has been rescheduled for Saturday August 21.
The GAA said the decision had been made "following a status report received by the GAA relating to positive Covid cases in the Tyrone panel".
It is understood that around a third of the Tyrone panel was missing from a weekend training session having either tested positive or been forced to self isolate.
The date of the All-Ireland final has also been changed as a result. it will not be played on Saturday September 4.
The football U20 final meeting of Offaly and Roscommon will go ahead at Croke Park on Sunday with the same permitted attendance.
"The GAA will continue to liaise with the appropriate government departments and officials to discuss the practicalities of having these revised fixtures included under the statutory instrument that has facilitated the increased attendances of recent weeks," the organisation said.
"The GAA will also be working with the LGFA around the TG4 Ladies All Ireland Junior final scheduled for Croke Park on September 4."
The pandemic had already caused the under 20 hurling final between Cork and Galway to be rearranged for Tuesday August 18 after a Cork player tested positive.
