He is definetly out for Saturday's midday trip to Bolton's Reebok Stadium, and may well be out for the majority of the season.
Chelsea have also registered the highly promising youth goalie, Yves Makabu-Makalambay, with the Premier League. He has been in outstanding recent form and has been given the squad number 50!
Little else is known about Carlo's recent injury, but Chelsea Mad will keep you informed as more becomes clear!