Iñaki, who was named Man of the Match for his impressive performance, said the win proved to the world that Athletic are a match for any side.
“I’m very happy,” Williams said after the final. “But I still haven’t processed what we just did.
“We showed we can compete with any other team. They couldn’t knock us down.
“Personally, I’m very happy. When I needed to turn up, I was there and the ball went in.
“It’s the reward for all the work I’ve been doing.”
The striker said it was hard work and a refusal to give up that saw Athletic over the line.
“The effort made and fatigue didn’t get the better of us,” he added. “We never accept defeat. That’s our style. And when we fight and battle together, we’re very difficult to beat.
“We showed that we’re a great team and this is dedicated to all Athletic fans.
“When you have heart and faith, all is possible. We’ve worked like animals and we’ve been rewarded for it.
“I think we’re deserved winners of this Super Cup.”
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Draw on the road against Real Betis
Athletic troubled Bravo in the final stretch of a game in which they had an extra player for 80 minutes due to Fekir’s dismissal
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Iñigo Martínez medical report
The player has not travelled to Seville for Wednesday night’s match against Real Betis
First team medical report
Yeray Alvarez, Yuri Berchiche and Iker Muniain join the injury list and will not be available for Wednesday’s match against Real Betis
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Marcelino wants the team to “recover mentally” and “compete at the highest possible level” until the end of the season
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