Chelsea boss Maurizio Sarri said Kepa Arrizabalaga's refusal to come off during the Carabao Cup final defeat to Manchester City was due to a "big misunderstanding".
Arrizabalaga defied his manager's orders late in extra time after receiving treatment for an apparent bout of cramp, despite the fourth official putting up his number on the board and Willy Caballero being primed to come on.
After the Spaniard, who was within his rights to decline the substitution according to International Football Association Board (IFAB) rules, stood his ground, Sarri stormed off down the tunnel, furious that the change was not made.
Arrizabalaga stayed on the pitch as the first trophy of the season was decided by a penalty shootout after 120 goalless minutes at Wembley.
He saved Leroy Sane's spot-kick, but City still won the competition thanks to Raheem Sterling's decisive kick sealing a 4-3 win.
Sarri revealed after the match that he thought his goalkeeper was suffering from cramp, wanting to swap him for Caballero, and only found out he was not injured after the incident.
"It was a big misunderstanding, I understood that he had cramp so I didn't want the goalkeeper to go to the penalties in that physical condition," Sarri said.
"Then I realised the situation when only the doctor arrived to the bench after four minutes and in the meantime I wanted Caballero on the pitch.
"The goalkeeper only wanted to let me know that he was in condition to go to the penalties. It was a big misunderstanding."
Even if it was a misunderstanding, Arrizabalaga still appeared to show Sarri a huge amount of disrespect, which does little to quell the suggestion that the under-pressure Italian does not have control of his dressing room.
The former Atletico Madrid keeper will not face any disciplinary action.
"Kepa was right, but wrong in the way he conducted himself," Sarri added.
"Mentally he was right, he was able to go to the penalties. He was right for the motivation but not for the conduct.
"I was really angry. I want to talk with him because he needs to understand that we can get in trouble, especially with you (the media).
"I have to explain the situation to Kepa but without any other problem."
After setting up for the Wembley final in a manner that would allow no repeat of their 6-0 Premier League humiliation of just a couple of weeks ago, Chelsea put up a good show and improved as the game went on.
They restricted City to very few clear-cut chances and could have snatched a winner towards the end of normal time.
Despite Arrizabalaga's actions, Sarri insists the performance shows Chelsea's players are behind their manager.
"After this match I have to say that I'm sure," he said. "Because they played exactly what I asked. Today I am proud of my players.
"You have to ask the club (about the future), here I am really very happy. I think in the last three matches we are improving, we have improved a lot.
"Today we showed to everyone that we could become a very solid team, because we conceded nothing to the opponents, against Man City that is not easy.
"So I'm really very happy with my players and today I'm proud of my players."