London Irish players and staff have yet to receive their April wages amid concern about the Premiership club's financial future.
The players were told on Tuesday they would be paid that day, but funds had still not arrived on Wednesday morning.
London Irish are in the process of a protracted takeover by an American consortium.
The players have been called to a meeting on Wednesday lunchtime for a further update.
Wages were due on Monday, with the delay being attributed to a bank holiday, new company bank accounts and money being transferred from the United States.
But the situation is reminiscent of what happened at Worcester and Wasps earlier this season, with both clubs struggling to pay wages before going into administration and subsequently out of business.
However, the chief executive of Premiership Rugby, Simon Massie-Taylor, is confident Irish can move forward if the takeover goes through.
"I do think it's different [to the situations at Worcester and Wasps]," he told BBC Radio 5 Live on Tuesday.
"Between Premiership Rugby and the RFU (Rugby Football Union), we've been engaged for quite a while with both the current ownership and the future buyers and there are lots of very positive signals coming from both sides.
"It's been reported that the new ownership have been in front of the players and the staff last week and today [Tuesday], which is a positive signal of their intent.
"And if it comes off then clearly you've got a new breed of investor. They're from across the pond and they've got interest in other sports so it is a positive news story."