Read on for all of the reaction and how the extraordinary incident at the end of extra-time played out.
'Kepa should be sacked'
Chris Sutton
Ex-Chelsea striker on BBC Radio 5 live
Getty ImagesCopyright: Getty Images
Kepa should never play for Chelsea again. that should be his last performance in a Chelsea shirt. He's a disgrace. I've never seen anything like it.
if I was Sarri I would walk. You cannot be undermined. Why weren't the players dragging Kepa off anyway?
Kepa should be sacked, not Sarri.
It was a misunderstanding - Sarri
Chelsea
ReutersCopyright: Reuters
Chelsea manager Maurizio Sarri says that extraordinary stand-off with keeper Kepa Arrizabalaga was a "misunderstanding".
Sarri also says the Spaniard will not be disciplined by the club.
"I misunderstood the problem and only realised the situation when the doctor arrived at the bench.
"It was a big misunderstanding because I understood the keeper had cramp and was unable to go to the penalties. But it was not cramp and could go to the penalties."
On why he walked off towards the tunnel: "I needed to return to be quiet. He [Kepa] understood that I asked for a change for his physical problem and he said I haven't a physical problem. And he was right.
"I realised after when the doctor arrived. I have talked to him [Kepa] but only to clarify because now I have understand the situation."
What happened?
Have you ever seen anything like it?
A player refusing to go off - and his manager losing the plot.
Chelsea goalkeeper Kepa Arrizabalaga resisted Maurizio Sarri's attempt to substitute him late in extra-time of the Carabao Cup final, which left his manager seething on the touchline.
What a night! I'm sure we haven't heard the last of this. A reminder that Chelsea play Tottenham on Wednesday...
I've still got authority - Sarri
Chelsea
Chelsea manager Maurizio Sarri says his future at Stamford Bridge is "the same" as it was before the match.
The Italian insists he still has the backing of the players and retains authority in the dressing room.
"After this match I have to say that I'm sure of that because they played exactly what I asked. Today I am proud of the players," he said.
Does this incident put his future under more doubt? "You have to ask the club. Here I am very happy and in the last three matches we are improving and have improved a lot.
"Today showed everyone we could be a very solid team because we conceded nothing to the opponents and to Manchester City that is not easy. I am happy with my players.
"I think the club would be proud of that performance too, because the performance was very good against, in my opinion, the best club in Europe."
'No way back'
Chelsea 0-0 Man City
Chris Sutton
Ex-Chelsea striker on BBC Radio 5 live
How will Willy Caballero feel after that? How can he train with Kepa again? How can Sarri stand in a dressing room and speak to that player again and expect him to listen to him? There's no way back for Kepa.
Ashley: Kepa should be banned by Chelsea for at least 5 games..player power rules over a manager? Pathetic behaviour from him. I'll back Sarri on this one because there is a massive lack of disrespect there.
Amrul: If Sarri escapes this it would be because of Public sympathy. Kepa is now the villain of the piece at Stamford Bridge.
'He's protecting his player'
ReutersCopyright: Reuters
Former Chelsea captain John Terry on Sky Sports: "He's protecting his player. Whether that hs been dealt with inside the dressing room, I don't know. Publicly that's his approach."
It was a misunderstanding - Sarri
Chelsea
ReutersCopyright: Reuters
Chelsea manager Maurizio Sarri says that extraordinary stand-off with keeper Kepa Arrizabalaga was a "misunderstanding".
Sarri also says the Spaniard will not be disciplined by the club.
"I misunderstood the problem and only realised the situation when the doctor arrived at the bench.
"It was a big misunderstanding because I understood the keeper had cramp and was unable to go to the penalties. But it was not cramp and could go to the penalties."
On why he walked off towards the tunnel: "I needed to return to be quiet. He [Kepa] understood that I asked for a change for his physical problem and he said I haven't a physical problem. And he was right.
"I realised after when the doctor arrived. I have talked to him [Kepa] but only to clarify because now I have understand the situation."
Get Involved
#bbcfootball or 81111 on text
Nicola: I do feel sorry for Sarri... He seemed to soften his stubbornness today with the lineup and the substitutions and the second half performance was brilliant... But then that Kepa incident happens and undermines everything and I wouldn't blame him for walking.
Paul: As bad as Kepa behaved let's be honest, as a player he has more value as a commodity to Chelsea than sarri does as a manager. It's a club who've still won loads despite sacking managers. Sarri won't be missed, Kepa could play for a decade. Sarri will be one who goes.
Post update
Maurizio Sarri is back-pedalling fast here. He is now saying that there is no problem between him and Kepa as he now understands that Kepa did not need to come off.
It seems a bizarre stance to me...
'I can't comment'
Chelsea
Chelsea skipper Cesar Azpilicueta straight bats the only question we all want his answer to...
On the incident between Kepa and Sarri: "I don't know what happened because I was on the other side of the pitch so I can't comment."
On Chelsea's performance: "Obviously we knew we had to fight very hard against a very strong team and to have chances to win the trophy we got to penalties and we are very disappointed. Now we have to recover because 120 minutes was very hard and we have another tough game in midweek.
"First of all we had a very good effort from everyone involved, we ran a lot and we fought a lot, but maybe it is true we lacked a bit with ball but we had chances as well."
On where Chelsea go from here: "We are used to competing in the biggest fixtures and fighting for trophies but we are frustrated because we have not showed consistency.
"Now we have to be focused and play for the Europa League and to qualify for the Champions Legaue so hoepfully everyone, we are ready for it."
Post update
Mauizio Sarri calls it all "A big misunderstanding, Kepa was able to continue."
'Whole team disrespected Sarri'
Chelsea 0-0 Man City
Chris Sutton
Ex-Chelsea striker on BBC Radio 5 live
In the heat of the moment there, in virtually any other team, the players would have dragged him off. What does that tell us about Chelsea at the moment? It's not just Kepa who has disrespected Sarri there, it's the Chelsea players.
Post update
Here is Sarri...
Post update
Maurizio Sarri has yet to face the media. Unsurprisingly.
'Players should have dragged Kepa off'
Chris Sutton
Ex-Chelsea striker on BBC Radio 5 live
I've seen players disgruntled before and throw a boot or their shirt down when they're taken off but players know the rules.
They abide by the decision and if you're going to have a row you have it in the dressing room. That is unprecedented, what we have seen today and Kepa has to go.
The players didn't want anything to do with it - they should have dragged him off.
Post update
Getty ImagesCopyright: Getty Images
Two of the four finals
involving Manchester City’s Pep Guardiola as a manager to have gone to
penalties have been against Chelsea, with Guardiola winning both (also
2013 Super Cup with Bayern Munich).
Live Reporting
Tom Rostance
All times stated are UK
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Latest PostGood night
Nowhere to go from there but home!
Here's the match report.
Read on for all of the reaction and how the extraordinary incident at the end of extra-time played out.
'Kepa should be sacked'
Chris Sutton
Ex-Chelsea striker on BBC Radio 5 live
Kepa should never play for Chelsea again. that should be his last performance in a Chelsea shirt. He's a disgrace. I've never seen anything like it.
if I was Sarri I would walk. You cannot be undermined. Why weren't the players dragging Kepa off anyway?
Kepa should be sacked, not Sarri.
It was a misunderstanding - Sarri
Chelsea
Chelsea manager Maurizio Sarri says that extraordinary stand-off with keeper Kepa Arrizabalaga was a "misunderstanding".
Sarri also says the Spaniard will not be disciplined by the club.
"I misunderstood the problem and only realised the situation when the doctor arrived at the bench.
"It was a big misunderstanding because I understood the keeper had cramp and was unable to go to the penalties. But it was not cramp and could go to the penalties."
On why he walked off towards the tunnel: "I needed to return to be quiet. He [Kepa] understood that I asked for a change for his physical problem and he said I haven't a physical problem. And he was right.
"I realised after when the doctor arrived. I have talked to him [Kepa] but only to clarify because now I have understand the situation."
What happened?
Have you ever seen anything like it?
A player refusing to go off - and his manager losing the plot.
Chelsea goalkeeper Kepa Arrizabalaga resisted Maurizio Sarri's attempt to substitute him late in extra-time of the Carabao Cup final, which left his manager seething on the touchline.
Here's how it all unfolded
Post update
What a night! I'm sure we haven't heard the last of this. A reminder that Chelsea play Tottenham on Wednesday...
I've still got authority - Sarri
Chelsea
Chelsea manager Maurizio Sarri says his future at Stamford Bridge is "the same" as it was before the match.
The Italian insists he still has the backing of the players and retains authority in the dressing room.
"After this match I have to say that I'm sure of that because they played exactly what I asked. Today I am proud of the players," he said.
Does this incident put his future under more doubt? "You have to ask the club. Here I am very happy and in the last three matches we are improving and have improved a lot.
"Today showed everyone we could be a very solid team because we conceded nothing to the opponents and to Manchester City that is not easy. I am happy with my players.
"I think the club would be proud of that performance too, because the performance was very good against, in my opinion, the best club in Europe."
'No way back'
Chelsea 0-0 Man City
Chris Sutton
Ex-Chelsea striker on BBC Radio 5 live
How will Willy Caballero feel after that? How can he train with Kepa again? How can Sarri stand in a dressing room and speak to that player again and expect him to listen to him? There's no way back for Kepa.
Chelsea double down
Nothing to see here.
Move right along...
Get Involved
#bbcfootball or 81111 on text
Ashley: Kepa should be banned by Chelsea for at least 5 games..player power rules over a manager? Pathetic behaviour from him. I'll back Sarri on this one because there is a massive lack of disrespect there.
Amrul: If Sarri escapes this it would be because of Public sympathy. Kepa is now the villain of the piece at Stamford Bridge.
'He's protecting his player'
Former Chelsea captain John Terry on Sky Sports: "He's protecting his player. Whether that hs been dealt with inside the dressing room, I don't know. Publicly that's his approach."
It was a misunderstanding - Sarri
Chelsea
Chelsea manager Maurizio Sarri says that extraordinary stand-off with keeper Kepa Arrizabalaga was a "misunderstanding".
Sarri also says the Spaniard will not be disciplined by the club.
"I misunderstood the problem and only realised the situation when the doctor arrived at the bench.
"It was a big misunderstanding because I understood the keeper had cramp and was unable to go to the penalties. But it was not cramp and could go to the penalties."
On why he walked off towards the tunnel: "I needed to return to be quiet. He [Kepa] understood that I asked for a change for his physical problem and he said I haven't a physical problem. And he was right.
"I realised after when the doctor arrived. I have talked to him [Kepa] but only to clarify because now I have understand the situation."
Get Involved
#bbcfootball or 81111 on text
Nicola: I do feel sorry for Sarri... He seemed to soften his stubbornness today with the lineup and the substitutions and the second half performance was brilliant... But then that Kepa incident happens and undermines everything and I wouldn't blame him for walking.
Paul: As bad as Kepa behaved let's be honest, as a player he has more value as a commodity to Chelsea than sarri does as a manager. It's a club who've still won loads despite sacking managers. Sarri won't be missed, Kepa could play for a decade. Sarri will be one who goes.
Post update
Maurizio Sarri is back-pedalling fast here. He is now saying that there is no problem between him and Kepa as he now understands that Kepa did not need to come off.
It seems a bizarre stance to me...
'I can't comment'
Chelsea
Chelsea skipper Cesar Azpilicueta straight bats the only question we all want his answer to...
On the incident between Kepa and Sarri: "I don't know what happened because I was on the other side of the pitch so I can't comment."
On Chelsea's performance: "Obviously we knew we had to fight very hard against a very strong team and to have chances to win the trophy we got to penalties and we are very disappointed. Now we have to recover because 120 minutes was very hard and we have another tough game in midweek.
"First of all we had a very good effort from everyone involved, we ran a lot and we fought a lot, but maybe it is true we lacked a bit with ball but we had chances as well."
On where Chelsea go from here: "We are used to competing in the biggest fixtures and fighting for trophies but we are frustrated because we have not showed consistency.
"Now we have to be focused and play for the Europa League and to qualify for the Champions Legaue so hoepfully everyone, we are ready for it."
Post update
Mauizio Sarri calls it all "A big misunderstanding, Kepa was able to continue."
'Whole team disrespected Sarri'
Chelsea 0-0 Man City
Chris Sutton
Ex-Chelsea striker on BBC Radio 5 live
In the heat of the moment there, in virtually any other team, the players would have dragged him off. What does that tell us about Chelsea at the moment? It's not just Kepa who has disrespected Sarri there, it's the Chelsea players.
Post update
Here is Sarri...
Post update
Maurizio Sarri has yet to face the media. Unsurprisingly.
'Players should have dragged Kepa off'
Chris Sutton
Ex-Chelsea striker on BBC Radio 5 live
I've seen players disgruntled before and throw a boot or their shirt down when they're taken off but players know the rules.
They abide by the decision and if you're going to have a row you have it in the dressing room. That is unprecedented, what we have seen today and Kepa has to go.
The players didn't want anything to do with it - they should have dragged him off.
Post update
Two of the four finals involving Manchester City’s Pep Guardiola as a manager to have gone to penalties have been against Chelsea, with Guardiola winning both (also 2013 Super Cup with Bayern Munich).