Pep Guardiola queried how effective the new protocols for Covid-19 can be in preventing contact on the pitch after Manchester City's FA Cup win over Birmingham.
With more regular testing introduced recently across clubs following outbreaks including Newcastle, City, and Fulham, the PFA this week reminded all players not to celebrate with teammates at goals or swap shirts at the end of games in a bid to reduce contact and keep infection rates down.
Such instinctive reactions have proven difficult to shake off even days after getting the message, with countless examples in the FA Cup this weekend of players of teams coming together to mark goals and also scenes of shirt-swapping at the conclusion of matches.
Sergio Aguero added to what has been a chaotic three weeks for City thanks to Covid-19 as he was unavailable to face Birmingham and has to self-isolate after coming into too much contact with someone who has tested positive.
It is currently unclear whether Aguero can test his way out of isolation given the players are given the green light to play whenever they get a positive test, and Guardiola echoed the uncertainty that exists across the sport as they try to carry on while much of society is locked down.
"We are going to follow the protocols," said Guardiola.
"But when one guy scores a goal, I don't know if they can be controlled.
"We are playing a game because all of us tested negative.
"I don't know what is going to happen but when someone scores a goal I don't know if he's going to think he's unable to hug his mate for two or three seconds.
"Sergio was in contact with one person and must be isolated - that is good. But we were in touch with Sergio as well and we played. I don't know.
