Rio Ferdinand was helped out of the Riverside last night with his injured left foot encased in a plastic surgical boot and Chelsea's title hopes seemingly being revived with his every faltering step.
The Manchester United central defender and current England captain sustained the injury, which will almost certainly rule him out of Wednesday's Champions League game at home to AS Roma, during a thrilling 2-2 draw against Middlesbrough.
Ferdinand's second-half injury saw Ferguson forced to send the inexperienced Gerard Pique on in his stead after allowing the limping England defender to spend 15 minutes trying to run the problem off.
His absence would all the more concerning after injury in the first leg in Rome ruled fellow central defender Nemanja Vidic out for a number of weeks.
"Hopefully it's not too serious with Rio," said Ferguson as Ferdinand's foot was strapped and booted ahead of scans this morning. "He was limping too long though and the danger is that, if we'd left him on, things could have been worse."
United sources later said Ferdinand had "no chance" of facing Roma - against whom Ferguson's side have a 2-0 first-leg lead - and is doubtful for Sunday when Arsenal visit Old Trafford.
Without their first choice central defensive pairing, the meanest in the league this year, United would be forced to start with two of John O'Shea, Wes Brown and Pique, with the latter likely to miss out.