The AFL has opted to relocate Sydney and GWS to Queensland as concern grows about the latest COVID-19 outbreak in Victoria.
Both clubs have been based in Victoria since June 22 due to NSW's coronavirus crisis but were told late on Wednesday night about their next impending move.
The Sydney teams were meant to play their derby in Ballarat on Saturday but that is now likely to be played at the Gabba in Brisbane.
GWS and the Swans, as well as the Western Bulldogs who are due to play Gold Coast on Saturday, will fly out of Melbourne on Thursday.
The Brisbane Lions flew to Victoria on Wednesday ahead of Friday night's clash with Richmond at the MCG.
AFL meetings on Thursday will decide what happens with the remainder of round 18 as exposure sites in Victoria continue to be added.