Charlton boss Alan Pardew has told Cardiff they will have to increase their offer to have any hope of signing Marcus Bent.
The striker, who spent last season on loan in the Premier League with Wigan, looks set to leave The Valley this summer.
Championship rivals Cardiff have made two bids as they look to secure Bent's services, but Pardew insists the Addicks' valuation of the player is still to be met.
He told Sky Sports News: "With all due respect it's a good bid but we feel his market value is worth more than that - especially the season he had at Wigan.
"So Marcus' market value is certainly more than what Cardiff have bid at the moment."
Pardew also confirmed that Algeria defender Madjid Bougherra is a target for Spanish side Real Betis, but the two clubs are yet to agree on a fee.
Meanwhile, summer signing Mark Hudson is confident that Charlton will be among the Championship's promotion contenders.
He said: "We've got as good a chance as anyone. We've got a great bunch of lads who are all wanting to go in the right direction and hopefully we can bring in a few more who are wanting to do the same.
"There's going be five, six or seven clubs challenging to go up. Palace are going to be there, along with Wolves, Derby and Birmingham.
"It's going to be a tough season, but it's always like that in the Championship. We're aware of that and we'll give it our best shot."