It’s the first time City have ever won the competition with qualification for this showpiece occasion coming through June’s Champions League success.
It was also Walker’s first trophy with the armband on after Treble winning skipper Ilkay Gundogan moved on in the summer.
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We held our nerve to score all five spot kicks before Sevilla’s Nemanja Gudelj struck the bar to hand us the trophy.
It had already been a dramatic night in Athens, with the Europa League winners taking the lead in the first half thanks to a towering Youssef En-Nesyri header.
Ederson was then called upon to make a number of decisive interventions before Cole Palmer got his head on a Rodrigo cross to level the scores.
We push for the victory from that point, but had to wait until the end of the shootout to confirm our maiden UEFA Super Cup success.
Check out the historic moment via the video above...