Birmingham City have rejected a £4million offer from West Ham United for defender Matthew Upson.
The England international is fast emerging as one of the most sought-after properties in the January transfer window, with West Ham having firmed up initial interest with an official offer.
Alan Curbishley's bid has, though, fallen on deaf ears at St Andrews - with the Championship table toppers valuing Upson, whose contract expires in 18 months' time, at around the £6million mark.
West Ham are desperate to add to their squad in a bid to quell an alarming slump this season, which has seen them very much embedded in the battle to beat the drop.
While they continue to struggle, Birmingham look strong bets for promotion and having reiterated their Premiership credentials with a 5-1 FA Cup win at Newcastle on Wednesday, they have no intention of sanctioning the departure of top names cheaply.
Upson's former club Arsenal are entitled to a 25 per cent cut of any transfer fee above the £2.5million Birmingham paid for him in 2003, further increasing the necessity for them to demand a top price.