The US No.1 admits he was unhappy with the way Chelsea scored what would be the only goal of the game, but he will bounce back stronger from the experience.
"It's a tough one," he said. "I think the boys did a good job, Chelsea are a tough team to play and their goal was indecision on my hands and I'll learn from it.
"You have to keep going and I'm proud of how the boys fought and didn't give up.
"The good thing is there is another game in three or four days so we can't get too low on this one.
"We have to learn from it, come back together as a team and be ready for the next one."
Watch Zack's full interview on the video above...
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