Updated at 9.20pm

Chelsea goalkeeper Kepa Arrizabalaga ignored manager Maurizio Sarri's decision to substitute him before a penalty shootout as the League Cup final went to spot-kicks on Sunday to cast more doubt on the Italian's future.

With Sarri reportedly on the brink of being sacked amid talk of Chelsea's players losing faith with him, there was very public evidence that the Italian doesn't have the respect of at least one member of his squad.

When Kepa needed treatment late in extra-time, the second time he had called for assistance in the match, it seemed the Spaniard would be substituted as Willy Caballero walked to the touchline in preparation to come on.

But Kepa eventually climbed to his feet and signalled that he was fit enough to carry on.

Sarri disagreed and waved for Kepa to come off.

Incredibly, Kepa refused and stood in his penalty area while Sarri lost his cool, ranting in disbelief at the challenge to his authority, briefly storming down the tunnel and having to be held back by Chelsea defender Antonio Rudiger when he went to confront him before the penalty shoot-out.

It was a spectacular meltdown that epitomised everything that has gone wrong for Sarri in his troubled first season in charge.

Kepa did save one penalty during the shoot-out, which Chelsea ultimately lost, but that is unlikely to be enough to save him from Sarri's wrath after a row that could easily cost his manager his job.

Speaking during a post-match interview, Sarri played down the incident. 

"It was a misunderstanding," the Chelsea manager said. "I understood he had cramp and I didn't want the goalkeeper to go to penalties in that physical condition. Kepa was right but the way he behaved was wrong".