To rub salt into the wounds, a Chelsea fan refused to shake Kepa Arrizabala's hand after the full-time whistle following the incident where he refused to be substituted.
Kepa, who was called to be subbed off for Willy Caballero in extra time, decided to tell manager Maurizio Sarri that he didn't want to be replaced in a remarkable set of circumstances.
Chelsea went on to lose the penalty shoot out, with the Spaniard failing to save a relatively easy shot from Sergio Aguero, and the rest is history.
Should he have saved it?
Arrizabala's conduct was slated both during and after the game, and a moment when he walked down the Wembley stairs sums up his disastrous League Cup final appearance.
As you can see in the footage below, this Chelsea supporter shook every player's hand as they returned to the dressing room, including the likes of Eden Hazard and N'Golo Kante.
But he decided against shaking Kepa's hand.
Following on from the match, Sarri said that the whole incident was a "big misunderstanding" in his post match interview:
"I wanted Caballero on the pitch, but the goalkeeper wanted to let me know he was in [a] condition to go to the penalties," he said.
"It was a misunderstanding. Kepa was right, but in the wrong way he conducted himself.
"I thought Kepa was unable to go to penalties. I wanted Caballero on the pitch because I was afraid of his cramp, but the doctor explained it wasn't [a] cramp."
Thoughts on the incident? Should he be banned for his refusal to be subbed?
Let us know in the comments below.