Leigh's home game against Warrington on Thursday has become the latest fixture in the Betfred Super League to fall victim to the rise in Covid-19 cases.
The Wolves, who have a number of players still unavailable following the outbreak which led to the postponement of their last fixture against Hull KR, reported another positive test on Monday which took the number of players ruled out to nine, one of whom is a close contact and therefore also required to isolate.
Under the Rugby Football League's coronavirus protocols, a club can apply for a postponement if they have seven or more of their 25 best-paid players ruled out as a result of Covid-19.
The clubs will now liaise with the RFL about a possible rearrangement of the fixture, although that seems unlikely to happen.
It takes the number of games called off in the last seven weeks to 13, including two that were cancelled due to clubs being unable to raise a team.
On the day most lockdown restrictions were lifted and Super League clubs began preparing to welcome full crowds back to the game, the latest development is a reminder that normality is some way off.
It further justifies the Rugby Football League's decision to use win percentage to determine league placings in case not all fixtures are fulfilled but, as it currently stands, clubs still need to play a minimum of 18 matches to qualify for the play-offs.
Hull KR, whose derby with Hull FC has been postponed twice, have so far played only 10 games even though clubs have entered the second half of the season.
Challenge Cup finalists Castleford's clash with Catalans Dragons on Saturday is also in doubt due to positive Covid-19 cases in the Tigers camp.
The club have reported three positive tests, one of them involving a player who played against St Helens.
As a result, all 21 players who travelled on the coach to Wembley, as well as the coaching staff, have been told to isolate until further notice and the club will undergo a further round of PCR testing on Tuesday.