Celtic manager Neil Lennon has called Boli Bolingoli's behaviour a "total betrayal of trust".
Lennon is furious with the defender, who breached quarantine rules by flying to Spain without informing the club, failing to isolate upon returning to the country and playing against Kilmarnock at Rugby Park on Sunday.
First Minister Nicola Sturgeon has since said that fans should not expect Celtic to play in the next week, while the club issued a statement condemning Bolingoli's "stupidity".
Speaking on Tuesday afternoon, Lennon expressed his anger.
As reported by STV journalist Ronnie Charters, Lennon said: “We gave players a couple of days off after Hamilton. We made it clear to players they were not to leave Glasgow. Boli took flight to Spain on Monday and kept it to himself...we were livid, appalled.
“We have been bitterly let down by an individual. I didn’t want to hear his excuse. He has blatantly disregarded our instructions.”
“There’s anger and disappointment from the squad. It’s just simply not good enough and it’s disrupted our plans.
“This is a rogue who has gone off tangent and has done something very very selfish. We have been completely oblivious to this. I’m absolutely livid. It’s a total betrayal of our trust.”
Asked if Bolingoli could be welcomed back into the Celtic squad, Lennon said: “Put it this way, I will find it very very difficult.”
