London Welsh have gone into administration and admit they have only enough money to survive one more month.
The Championship side have appointed administrators Tenon Recovery after conceding that they need an extra £1m to £1.5m to operate each season.
Formed in 1885, the Exiles can list more than 150 internationals among their former players, including Welsh greats JPR Williams and Gerald Davies.
The decision could see the men from Old Deer Park drop out of the second tier.
An official club statement read: "The club recently made the decision to turn professional and has developed a three-year plan to reach the Guinness Premiership.
"However, investment in top-quality players and experienced training and coaching staff has come at great personal cost to the principal investor and chairman, Kelvin Bryon.
"For London Welsh to progress towards promotion to the Premiership, the club will need to secure additional investment from either another individual or a consortium of investors.
"There are sufficient funds available for the club to continue to operate for one more month but without additional income the club will be unable to continue to trade in its present form."
London Welsh are due to start their season with a trip to Bristol on 5 September.
Speaking to BBC London 94.9, Gareth Roberts from Tenon Recovery indicated that all is not lost for the Exiles.
"If I didn't feel there was a good chance of success I'd probably be talking in my capacity as liquidator," he said, "in which case the company would have ceased to trade. I'm confident there are sufficient potential investors out there.
"The main existing investor Kelvin Bryon, who has put in around £1m in the last year, is making funds available to me to meet the ongoing costs of the business, principally the players' wages for the next month.
"He must share my sense of optimism otherwise he wouldn't put his hands in his pockets.
"I think there is a very good chance of coming out the other end intact and seeing London Welsh in the Championship next season."