Hull FC will now play Leeds Rhinos on Thursday following the positive tests at Castleford Tigers.
Hull were due to have the week off, but three Castleford players tested positive for COVID 19, and a further six had to self isolate. That meant the Black and Whites had to come off standby.
This game will now be the Round 18 clash, meaning it will be classed as a home game for Hull instead of Leeds.
In the Round 18 slot, the game between Leeds and Castleford will take place. Further details will be announced in due course.
Executive Chairman Robert Elstone said: “Super League clubs have responded exceptionally well to the challenges presented by Covid-19 and Hull FC have provided another example of this here.
“By stepping in to fulfil a fixture at such short notice they are a credit to the competition and we appreciate the level of inconvenience the club has faced in meeting this request.”