The Manchester United winger believes his teammate was lucky not to be more seriously hurt by the missile thrown by a home supporter after Robin van Persie's late winning goal.
Ferdinand was celebrating Robin van Persie's winning goal in the 3-2 victory at the Etihad Stadium when he was hit by a coin thrown by a home supporter.
Both the Football Association and Greater Manchester Police are investigating the trouble and Young also explained that Wayne Rooney had faced similar hostility when taking a corner near the City fans.
"It could have taken Rio's eye out," Young told MUTV. "You've seen the cut on his head.
"When Wazza [Wayne Rooney] was taking a corner there were so many objects being thrown on to the pitch as well."
City goalkeeper Joe Hart needed to intervene when a fan invaded the pitch and ran towards Ferdinand after he had been cut.
"On another day, if the pitch had not been so wet, the fan who came on to the pitch wouldn't have slipped over and could have attacked Rio," Young added.