Bolton's Tal Ben Haim is rapidly emerging as the man to ease some of Chelsea's defensive woes as coach Jose Mourinho looks to strengthen a squad ravaged by injuries and poor individual form.

The 24-year-old Israel international is reportedly a leading contender to join Chelsea's ranks after their interest in Manchester City's Micah Richards appeared to wane.

Chelsea, as a matter of course, rarely comment on speculation but Mourinho made it clear at the weekend that the club will not be pushed into paying exorbitant fees for their transfer targets.

Their interest in Richards is thought to have baulked because of City's insistence the player is worth at least £18 million - although the champions have not made any offer for the emerging England star.

The pressure on Mourinho to act swiftly intensified after Dutch defender Khalid Boulahrouz damaged knee ligaments against Aston Villa on Tuesday.

Ben Haim's situation is markedly different to Richards as his contract runs out in the summer and although Bolton insist they want to keep him the player has, so far, remained unwilling to enter into negotiations about a new deal.

Bolton would almost certainly refuse to sanction any move to Stamford Bridge without obtaining at least £5 million for a player who cost them just £250,000 from Maccabi Tel Aviv in July 2004

He is already entitled to talk to other clubs outside the Barclays Premiership under Fifa rules and although Bolton remain committed to keeping him, they know he could walk away from the Reebok on a free transfer in the summer.

Chelsea have also been linked with Roma defender Philippe Mexes, according to Italian newspaper Il Messaggero.

They claim Chelsea, along Real Madrid and AC Milan, have made Roma aware of their interest in the France centre-back whose contract with the club runs out next year.

Chelsea's defensive worries will ease considerably with the return of captain John Terry either against Wycombe in the Carling Cup semi-final next Wednesday or Wigan a few days later in the Premiership.