The American keeper has played in every round so far and will continue to do so at Wembley on Saturday.
“Always, I have done this,” said Pep.
“Maybe tomorrow we will win or lose, I don't know, but if Zack doesn't play, I would lose the team.
“He is the keeper for the US national team. When he plays, he plays well. He trains good and he more than deserves to play. I am happy to give him the chance.
“He has the personality and composure.
“No keeper in the world is like Eddie. No keeper in the world has that quality with feet, short and long.
“I don't want Zack to do what Eddie does. I want him to save the balls, I want us to concede as few chances as possible. We trust him a lot."
Watch Guardiola’s press conference via the video above!
Live text updates will begin in our Matchday Centre at 15:30 (BST).
We’re Not Really Here gets under way at 16:25 (BST), with Shaun Goater and Richard Dunne joining us the studio and Shaun Wright-Phillips reporting from Wembley.
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