Chelsea chief executive Peter Kenyon has confirmed the club would be willing to consider an offer from West Ham for unsettled winger Shaun Wright-Phillips.
Kenyon revealed that the Hammers had already made an approach for the England international but that the figure was well below Chelsea's valuation.
West Ham are thought to be prepared to pay around £10million - a fee that would shatter the record fee of £7.25million they paid to land Dean Ashton from Norwich in January.
The Hammers will have money to spend in the January transfer market following the takeover of the club by Icelanders Eggert Magnusson and Bjorgolfur Gudmundsson but Chelsea want to recoup a fair proportion of the £21million they paid Manchester City for the winger in July 2005.
Kenyon said: 'There has been interest from West Ham and they have officially approached us.
'We're not in the position of having an offer but we've certainly had interest expressed from them.
'Our position is that we're not looking to sell our players but it we get an offer we'll have to look at it on a serious basis.'
Chelsea, meanwhile, are still waiting to see if Didier Drogba will be fit enough to face Manchester United in the biggest game of the season at Old Trafford on Sunday.
The Ivory Coast striker suffered an ankle injury in the Champions League defeat to Werder Bremen in midweek and he did not train on Friday.
The hype surrounding Sunday's clash between the two top sides in the Barclays Premiership has already begun with Manchester United midfielder Cristiano Ronaldo claiming that Chelsea are no better than last year despite the arrivals of Andriy Shevchenko and Michael Ballack.
But England midfielder Frank Lampard hit back at Ronaldo's words by claiming the pair would do their talking on the pitch instead.
Lampard said: 'We have got nothing to prove - especially players of the calibre of Shevchenko and Ballack with what they have done for us and throughout their careers. They talk on the pitch and they will go on and do that again.'
But while the rest of the footballing world is already hyping the game up into a potential title decider, Lampard was only too keen to play down such talk.
Lampard added: 'It's a must-not-lose game for us. Our intention is to win the game and if not then draw.
'Even if we lose, there is a long way to go. I've been impressed with United - they are playing well and top of the league. They have hardly dropped a point.
'I believe in us and the better team will be the one that wins the league. Win, lose or draw we have to keep looking at the bigger picture which is to win the league.
'It will be important to start well against United. They always come out flying. We have to start well and impose ourselves on the game.
'If we can do that and play our best, then I am confident we can beat any team.'
Lampard is determined to return from Old Trafford with some reward after their 1-0 defeat last season.
That setback was only their second league defeat under Jose Mourinho and arrived on the back of a 1-0 UEFA Champions loss to Real Betis - the first time the Portuguese coach had lost two games on the spin.
Lampard said: 'It was frustrating because we were on a very good run and we did not deserve to lose the game.
'We started slowly, which was our fault, and United always start with a high tempo - that's when they are at their best.
'In the second half we deserved to get something out of the game but we didn't. We have to beware of a slow start this time.'
The man charged with controlling the tempo of Sunday's clash is referee Howard Webb.
Lampard has already clashed with officials this season over comments concerning Chelsea discipline allegedly made to him by Graham Poll during their 2-1 defeat at Tottenham.
The Chelsea midfielder believes Webb is one of the best officials in the game but admits that it is hard for committed professionals to keep their tempers in check all the time.
Lampard said: 'You are asking top players, professionals, who are desperate to win games, to not ever get heated and get upset at certain things - that's hard to do.
'Of course, players have to carry themselves well and I think the only thing about surrounding the referee is that it can be done if you are speaking to him on a good basis.
'That's what we have to try and do - try and talk to him. Howard Webb is one of the best refs and we have to make sure we don't disrespect him.'