The Diamonds were due to host Barry Ferguson’s team but successfully applied for a cancellation with a number of players self-isolating. The SPFL granted a similar request from Ayr who were unable to name a squad due to the impact of virus restrictions on David Hopkin's squad.
A league spokesman said both were postponed “after reviewing the information provided” and “a further update will be provided in due course.”
The two clubs are not alone in being affected. Rangers flew out to Thursday’s Europa League play-off against Alashkert without several first-team players and manager Steven Gerrard. However, some may return to the fray at the weekend when Celtic visit Ibrox in the first Old Firm game of the season.
The cancellation also means Raith Rovers will have had 20 days between competitive matches following their lighting failure against Dunfermline last weekend.