Anti-doping chief warns Blues over blood-spinning
The alert was issued by Dick Pound, head of the World Anti-Doping Agency, following unsubstantiated reports that Chelsea had offered the treatment to Arjen Robben.
The process involves taking a sample of the athlete's blood, removing the platelets - the cells which assist the healing process - and then injecting them back into the injured area. It is claimed it speeds up recovery.
Pound warned: "It sounds like blood manipulation of some sort to me. But I would need to talk to our scientific department to get all the background."
Chelsea insist Paulo Ferreira could still play a part in the final chapter of their amazing season despite breaking a bone in his foot.
The Portugal full-back was injured on international duty in midweek and could be out of action for around five weeks, with Glen Johnson set to deputise.
However, with the league leaders still on course to add the Premiership and Champions League trophies to the Carling Cup, a statement on the club's website insisted "this does not mean his season is over."
Club doctor Bryan English revealed: "He has broken the fifth metatarsal in his right foot and it will be operated on tomorrow.
Manager Jose Mourinho will also be without Arjen Robben for today's late kick-off at Southampton.
Robben was also injured playing for Holland last weekend and, although scans have shown no fracture to the ankle, he is likely to be out of action for up to a month.
The game at Southampton will bring an end to a tumultuous week for the Stamford Bridge club in which they were fined for bringing the game into disrepute by UEFA.
The club have advised Mourinho not to appeal against his two-match touchline ban because they fear it could be increased.
The Chelsea boss was understood to be furious at being denied access to his team for both legs of their Champions League quarter-final tie against Bayern Munich.
But he is likely to accept the decision rather than risk seeing the ban increased. The club have the right to appeal against Mourinho's ban and their £33,000 fine but senior figures have urged caution.
The injuries leave Chelsea stretched as they face the most critical part of the season. Wayne Bridge will not play again this season after breaking his ankle against Newcastle during their FA Cup quarter-final exit.
Ferreira will be the third Blues player to suffer a fracture of the foot this season. Robben and Scott Parker suffered similar injuries and were sidelined for months as a result.
Southampton boss Harry Redknapp will be hoping 6ft 7in giant Peter Crouch can continue his rich scoring streak after scoring 13 goals in 18 games.
