Contingency dates have been agreed for the Super League play-offs should teams have to isolate due to Covid-19 cases.
A side with seven players out can request a postponement but will have to withdraw if they cannot fulfil either the original fixture or reserve date.
Warrington, who finished third, take on sixth-placed Hull FC on Thursday with Catalans Dragons (fourth) playing Leeds (fifth) on Friday in elimination games.
Huddersfield remain in training and would replace any side unable to play.
The Giants, who finished seventh, will undergo testing along with the other six clubs.
As part of its contingency plan, the Rugby Football League says possible reserve dates – expected to be next weekend – have been agreed with broadcasters Sky.
The winners of this week’s play-offs will then face Wigan and St Helens in the semi-finals on 19 and 20 November after they finished the season first and second respectively.
Should a semi-finalist or finalist not be able to play, they would be replaced by the highest-ranked losing side.
There is no reserve date for the Super League Grand Final on 27 November as clubs have stipulated the season must finish on that date.
The two beaten semi-finalists will continue to train should they be needed to replace a finalist.
The post-season was brought forward after Hull KR were forced to end their season early due to positive tests and has been extended to a six-team affair.