Exeter City manager Matt Taylor says he fears for the future of the League Two club's well-respected academy.
It has generated fees in excess of £4.5m in the past five years, but rules about how much top clubs have to pay for youth players means it may become less viable, according to Taylor.
Under the Elite Player Performance Plan (EPPP), top clubs pay a set rate for players up to the age of 16.
"If an academy stops generating money, it's harder to run," Taylor said.
The League Two club have produced players such as Brentford striker Ollie Watkins, Wales and Chelsea defender Ethan Ampadu and Swansea City captain Matt Grimes in the past few years.
But City reluctantly sold forward Jay Stansfield to Fulham in August after negotiating a fee above the EPPP threshold for the 16-year-old first-year scholar.
Highly-rated midfielder Ben Chrisene has reportedly caught the interest of Liverpool, Chelsea, Bayern Munich, Aston Villa and Southampton.
Chrisene became Exeter's youngest-ever player in August after featuring in City's 4-1 Carabao Cup loss to Coventry City aged 15 years, seven months and one day - beating a club record set by Ampadu.
He made his League Two debut as a late substitute in the 2-0 win over Cambridge United on Saturday, a day before his 16th birthday.
Under EPPP rules introduced in 2012, clubs would only need to pay Exeter - who have a Category Three academy - a fee of £12,500 for each year that a youth player has been under their tutelage.
Previously, fees were decided by tribunal.
The aim of the EPPP is to increase the number and quality of home-grown players making the step up to senior level.
"We're not going to get any more young players into our first team, not young players that are sellable assets, and that's the brutal reality of it," Taylor told BBC Sport.
"It's what this club's been run on for a number of years, but we can't protect our young players before they get to 16, if they don't sign a contract then our hands are tied and clubs can take them for what is a really small amount of money."
Taylor added: "Until the rules change or there's more value in having players leave us at 16, there's nothing we can do about it and because of our reputation the scouts are here, the agents are here."
|Compensation formula for academy players when joining another club|
|Age group of player||Category of club academy leaving||Applicable annual fixed fee - new club to pay|
|U9 to U11||All Categories||£3,000|
|U12 to U16||Category 1||£40,000|
|U12 to U16||Category 2||£25,000|
|U12 to U16||Category 3||£12,500|
Taylor hopes Chrisene will stay at Exeter and develop alongside the first team in the same way that previous successes from the club's academy did.
Watkins is seen as one of the brightest English prospects in the Championship, having scored 18 goals in 28 games for Brentford, Ampadu has won 13 caps for Wales and is currently on loan in Germany at Bundesliga side RB Leipzig, while Grimes is leading a Swansea side pushing for the Championship play-offs.
In all of those cases, the players went for deals well in excess of £1m having played a significant number of games in League Two for the Grecians.
"We've tried absolutely everything, educating the players, the parents, and emphasising what a good place Exeter City is for their development," Taylor added.
"They'll still get their move, and they'll probably get a better move off the back of it and play first-team football as opposed to getting caught up in one of the thousands of young academy players that don't play any first-team football.
"But they see the brighter lights of these bigger clubs and they go there. Financially they're better off, we can't compete with that. It's something the club will have to address, but it's also a real issue in football.
"We generate our own money, we've got no benefactor, no chairman handing out big sums of money saying 'go out and sign that player', any money going out has got to come in.
"The academy will always be important to us, but we've got to now look at different ways of generating money."