Leeds coach Richard Agar fears for rugby league's Wembley showpiece finals after witnessing the coronavirus pandemic strike at the heart of Super League once more.
Leeds' home game against St Helens and Wigan's trip to Huddersfield on Friday have both been postponed after an outbreak of Covid-19 at the Rhinos and the Giants.
There are now major doubts over Leeds' next scheduled fixture, which involves a trip to the south of France to play Catalans Dragons on Saturday week, and Agar is worried about the potential impact on the Challenge Cup and 1895 Cup finals at Wembley on July 17.
Castleford meet St Helens for the main prize at the national stadium while, in a curtain-raiser, York and Featherstone play in the second 1895 final.
The Rhinos won the 2020 Challenge Cup behind closed doors at Wembley in a final delayed until October with victory over Salford, who were without Dan Sarginson and Jack Ormondroyd after they failed Covid-19 tests.
"Having been there ourselves last year and knowing what the testing procedures are like, it's a big worry for me," Agar said.
"If the rate of infection keeps doubling, as it seems to have done, over the next three or four weeks, there's a wider implication for the sport and the impact it could have on those showpiece games.
"We know what it's like and Dan Sarginson could tell you about the anxieties around all that."
Two Leeds players have so far tested positive for Covid-19, forcing them to self-isolate for 10 days, and another seven have been shown to be close contacts through track and trace.
Under the Rugby Football League's Covid-19 protocols, a team can apply to postpone a match if seven or more senior players are unavailable and the governing body says it has accepted Leeds' request for the Headingley fixture.
Huddersfield were keen to play their game against Wigan despite having seven players test positive but Agar says he was left with just 14 available players, including two academy youngsters.
"It's genuinely impossible for us to field a team," he said. "We're in a pretty deflated place this morning.
"We went through it all last year when I don't think any club had it worse than us.
"Generally the feeling was we'd got through all that but clearly the new wave seems to be on its way.
"We bent over backwards to get every fixture fulfilled and the toll it took on this squad was unbelievable, it was last man standing.
"We're desperate to avoid the type of situation where we're playing four games in 14 days and five games in 20 days.
"The concern for me as a coach is that I'm losing a shed-load of players over the next 10 days.
"We're on the back of a good win and getting some momentum, so there's going to be a break which is incredibly frustrating and disappointing and worrying."
All four clubs will liaise with the RFL on possible re-arranged dates, although the table will again be determined by win points percentage to allow for the possibility of not all fixtures being fulfilled.
Huddersfield and Leeds, who were both forced to close their training ground for five days in January due to a spate of positive tests, were inactive last week after being knocked out of the Challenge Cup and gave their squad time off but Agar does not believe his players acted irresponsibly.
"We talked to the boys this morning about if there is a lull in relaxing protocols but we don't think there has been," Agar said.
"But the bottom line is that shops, restaurants and coffee shops are open, can we afford to go in any public places any more?"
Castleford coach Daryl Powell, who will lead his team out at Wembley in his final season with the club, admits players probably need to be more vigilant.
"Everybody is becoming a bit more relaxed about it at the moment for obvious reasons," he said. "We need to try and make sure we're looking after ourselves."
The Leeds game was due to be shown live by Sky Sports, who will now switch coverage to the match between Hull KR and Salford.