Swansea boss Steve Cooper is adamant Joe Rodon should not be sold "on the cheap" as Tottenham consider making a deadline-day move for the Wales defender.
Spurs have held talks with a view to signing Rodon, and could complete a deal before Friday's extended English Football League transfer deadline.
It has been reported, however, that the two clubs are some way apart in their valuation of the 22-year-old who impressed on Nations League duty for Wales this week.
Swansea believe Rodon is worth around £20million with Spurs' valuation near the £7m mark.
"What I would say about Joe or any other of our assets – and Joe is right up there as one of our biggest – it's really important that if we do end up having to sell then we get something to show for it," Cooper said.
"We shouldn't be selling on the cheap. The precedent has been set this year."
Referring to Ben Godfrey, the Norwich defender who recently joined Everton in a reported £25m deal, Cooper said: "The player is not a full international. Joe is and you have seen how well he played for Wales.
"If that's what the going rate is and that's the numbers getting bandied around, whether I agree or not, that's what it is.
"If we do lose an asset then our supporters will want to see some reinvestment and some good players coming in."
Andre Ayew has also been linked with a move to Brighton or West Brom before the deadline.
But Cooper said he was unaware of any approach for the Ghana forward, and he hopes to strengthen his threadbare squad before the transfer window closes.
But the deal appears to have foundered on Swansea's reluctance to pay a loan fee.
"I do like Harry a lot," Cooper said. "It's really good when you have worked with players through their development.
"The first time I tried to sign Harry was when he was under eight. I tried to get him at Wrexham but he had signed for Liverpool.
"I know Harry well, and his family, through his time at Liverpool and also where he grew up. It's not a million miles apart from where my family home is.
"I always follow the players I have worked with, stay in contact and let them know I am there if they need a bit of advice.
"Harry has had some good Championship experience and shown he is more than capable of excelling at that level.
"In the Premier League last year I think he scored seven goals, which is a good number in a team (Bournemouth) that got relegated."