The Nigerian defender declared himself fit to play in the Champions League last-16 tie hours after flying in from his country's win in the Africa Cup of Nations and was to blame for the Italians' opening goal, while also missing an excellent chance in the second half.
Commons, who was asked if too much was required of the defender after a long-haul flight from South Africa, answered: "Look, the manager picked him. The manager pulled him to one side and asked him if he was feeling okay. He said he was feeling brilliant. If he wasn't feeling okay then he should have said so. If he felt good then he should have put in a better performance."
Celtic's defence crumbled under second-half pressure, losing goals to Alessandro Matri, Claudio Marchesio and Mirko Vucinic. All the goals could be traced to errors and Commons said: "It was just very sloppy, individual mistakes – something you'd probably get away with on a playground, not in the last 16 of the Champions League. There are certain individuals who let the team down tonight.
"In the SPL you can get away with not quite playing. You can get away with just turning up and things happening. You can make mistakes and people don't punish you. At this level you clearly can't afford to make mistakes. If you do, you end up coming away with a 3-0 defeat.
"Hopefully this is just a one off. The back four have made errors which have probably cost us the tie. But it's partly down to them why we're here in the first place. It's just a bitter one to swallow."
He was also critical of Alberto Mallenco, the Spanish referee, who booked two Juventus players for incidents at corner kicks but did not judge any of the pushing or tugging worthy of a penalty.
"We didn't get the penalties, we didn't get our shots off and the result puts a dampener on the whole event," Commons said. "It's not just the referee. There is the linesman and assistant behind the goal too. Perhaps in an SPL game we'd get the penalty but tonight it happened too many times. The referee was aware it was happening. He did say to them a couple of times: 'If you do that again there will be a penalty,' but it never came."