Bolton's Tal Ben Haim is now 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, never comment on speculation but it is no secret the Blues 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 £18million - 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 £5million 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. Terry, recovering from keyhole surgery on his back, was never scheduled to play in a reserve team training ground friendly on Wednesday but continued his rehabilitation, working with rehabilitation physio Thierry Laurent. But Chelsea's squad also needs strengthening in attack where their reliance on Didier Drogba could prove costly as they attempt to reduce the six-point margin between themselves and Manchester United at the top of the league. Former Tottenham and West Ham striker Freddie Kanoute, now with Seville, is one name linked with a possible move to Stamford Bridge but the free-scoring striker, currently topping the goal charts in Spain, is another player Mourinho would baulk at paying an inflated price for. An injury to Drogba would leave Chelsea with just the misfiring Andriy Shevchenko and the inexperienced Salomon Kalou as back-up and neither, at the moment, appear to possess the firepower to keep the Blues in the hunt for a third successive title. Mourinho can enjoy the luxury of a relatively easy afternoon on Saturday when Chelsea host Macclesfield in the FA Cup third round - allowing him the opportunity to rest some of his regular first-team players. It will provide an opportunity for players like Wayne Bridge, Lassana Diarra and Mikel Jon Obi to enjoy another first team outing and full-back Bridge knows all too well they can be hard to come by. Bridge is kept out of Chelsea and England line-ups by Ashley Cole and while the left-back admits it is frustrating, he insists there is little room for self-pity. 'It's hard. If you talk to any player who isn't involved week-in, week-out, and just gets little chances here and there, they'd tell you that sometimes motivation can drop a little bit,' he said. 'But it comes with the territory of being at a club like this where the manager has lots of top quality options for each position. 'At Chelsea everyone works so hard in training, whether they are playing regularly or not and that means that when you do get a chance you're always ready. 'Sometimes your head can drop - that's only natural. But it's never for long. I've got family around me tom keep my spirits up and help me fight for my place.'