With Sunderland currently sitting bottom of the Premier League table, South Korean international Ki feels a win of this nature could be the catalyst for improved results for the remainder of the campaign.
"I think definitely it can help our league form. The atmosphere is buzzing among the boys and we all believe," the former Celtic star told the Shields Gazette.
"Chelsea are one of the best teams in England. Even though this is the League Cup, we don't care, because we'll get a lot of confidence from that.
"I think the boys were desperate to win. They had a lot of energy and we were fitter than Chelsea. We controlled the game in extra time.
"I can't express the feeling. It's my first goal in England, a quarter-final against Chelsea and scoring in the last minute. That's maybe a once in a lifetime experience.
"If we can beat Chelsea, we can beat other teams."
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