Chelsea must cough up £30million if they want to sign Andrew Robertson this summer, according to the Metro website.
The Blues are said to be keen on a player who cost Hull City just £2.85m from Dundee United last summer.
However, boss Steve Bruce suggesting his worth has increased significantly and has told chasing clubs they will have to pay up.
He said: ‘Luke Shaw went from Southampton to Manchester United after just one season in the top flight for £30m, and I rate Andy on a par with him as a young player with bags of ability and potential.
“We have already had calls from clubs asking to be kept informed about his situation, and it might become inevitable that he goes.’