John Terry will play in Sunday's Carling Cup final against Arsenal after making a remarkable recovery from the ankle injury he sustained against Porto.
The speed of Terry's recovery has surprised the club's medical department who had previously told Blues manager Jose Mourinho that his skipper would be available for the Portsmouth game next week.
Club doctor Bryan English, confirming the news in his latest medical update, said the England defender had 'ruptured an ankle ligament' against Porto and left the stadium on crutches.
Terry had an MRI scan on Thursday and started walking the same day.
English felt yesterday that Terry's injury would take 'five more days' to recover from and so informed Mourinho that Terry would not be available for selection in Cardiff.
But English revealed on Saturday that Terry 'felt a big improvement in his ankle and requested that the medical department performed a fitness test'.
Terry passed the test and then took part in a full training session paving the way for him to get the green light to play at the Millennium Stadium.
English added: 'This rate of recovery has surprised the medical department. I have apologised to Jose for providing him with misleading information that lead to his statements in relation to John Terry's injury yesterday.'
Chelsea received further good news from English on the fitness of winger Arjen Robben, who started against Porto but did not reappear for the second half after a hamstring tightened up.
English discovered that Robben's injury stemmed from a lower-back problem and when this was treated the Dutchman made a 'quick and full recovery'.
Meanwhile defender Khalid Boulahrouz, who dislocated his shoulder in the FA Cup fifth-round win over Norwich, could be back in training in 10 days but, according to English, will 'require stabilisation surgery at the end of the season'.
England midfielder Joe Cole is reported to be 'progressing well' following surgery for a navicular bone stress fracture in the foot and English predicts he will 'hopefully return to play at the end of March/early April.'