Kepa has endured a difficult few years and was left out of the Spain squad for Euro 2020 this summerKepa Arrizabalaga and a late substitution with penalties looming in a major cup final. Sound familiar?
In the 2019 Carabao Cup final against Manchester City, the £71m Spaniard refused to come off for Willy Caballero late in injury time, an incident which has so far been the defining moment of his time at Stamford Bridge.
He saved one penalty on that occasion but they still lost - and he was fined by the club for disobeying manager Maurizio Sarri's instructions.
On Wednesday, the roles were reversed, with Kepa the man to come on. This time, it was the Uefa Super Cup against Villarreal in Belfast, with the game tied at 1-1 after Gerard Moreno cancelled out Hakim Ziyech's opener. And this time it ended in glory.
It also helped that the man he replaced, Edouard Mendy - who had a good game - was more receptive to the idea.
Kepa was very active during the shootout, putting off opponents by getting in their faces and producing some theatrics on the goalline. It worked as he saved two penalties - from Aissa Mandi and Raul Albiol.
After he saved Albiol's kick, he was mobbed by jubilant team-mates who wanted to celebrate the moment with him.
Manager Thomas Tuchel, whose side were in the game after beating Manchester City in the Champions League final, revealed afterwards it has been an idea in the pipeline since February.
"It was not spontaneous," he told BT Sport. "We talked about it with the goalkeepers after the first cup game against Barnsley.
"Kepa has the best percentage at saving penalties. The analysing guys and goalkeeping coaches showed me the data. We spoke to the players and told them this could happen when we play in knockout games."
Mendy was gracious as he came off, embracing Kepa - and said in a post-match interview alongside Kepa he always knew it would happen.
Kepa came on as a 119th-minute substitute, saved two penalties and was booked"It's fantastic how Edouard accepted it," said Tuchel.
"He does not show the pride to not step off the field. He was happy to take this for the team."
Kepa, who lost his first-team place to Mendy last season, said: "It's not a typical situation but we arrived to penalties after Edouard did a fantastic job. Finally we won and we are so happy.
"I was ready because I knew this could happen. I tried to be ready, mentally and physically."
Mendy added: "I'm happy because we won. I knew since last year that if Kepa came on the pitch he would help the team."
BT Sport's pundits were impressed by Tuchel, Kepa and Mendy.
Former Chelsea midfielder Joe Cole said: "Thomas Tuchel can't miss. Everything he does works. We questioned him because of how well Mendy played but Kepa was fantastic in the shootout."
Former Chelsea forward Eni Aluko added: "This is the same Kepa who a few years ago nobody liked. He didn't look good. He's had an arc of a journey and is now a popular member of the squad."
Ex-England defender Rio Ferdinand said: "Kepa has been under immense scrutiny since he came to the club. You saw after his save what he means to this squad. They were all over him.
"Obviously Tuchel knew something we didn't. Before every penalty was taken he was right up in the face of the Villarreal players. He's got something about him. He has personality and character."
Kepa is not the first Spanish goalkeeper to make the headlines for an English club after a European final shootout against Villarreal this year. David de Gea missed from the spot in an epic Europa League climax as the Yellow Submarine beat Manchester United in May.
"Although there was a misunderstanding, on reflection, I made a big mistake with how I handled the situation" - Kepa apologised following the EFL Cup final in 2019
