Pulisic dominated the match and scored two goals as his side went on to beat Jurgen Klopp's men 3-1 during the pre-season encounter.
After a close opening 25 minutes, Virgil van Dijk opened the scoring for Liverpool with a powerful header following Andy Robertson's well-aimed cross.
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Karius has since made errors in Liverpool's pre-season games, including one against Borussia Dortmund in a friendly in the United States.
He was then denied the Man of the Match award on Sunday afternoon because, listen to this, the prize was sponsored by Heineken and with the legal drinking age at 21-years-old, he wasn't allowed to pick it up.
We'd love to see him in England, that's for sure. The German goalkeeper is reportedly unhappy with Liverpool's decision to sign a new goalkeeper and is now "considering his future" at the club.
Tickets for the El Clasico last year between Barcelona and Real Madrid sold for over US$10,000 each, although demand this year in the early stages of the competition hasn't been quite so high.
But Klopp was more positive about Daniel Sturridge, who fans must be hoping can finally put his injury curses behind him.
"He wants to be, I'm sure, the best Christian Pulisic he can be".
Next up for Liverpool is a game against Manchester City.
"I will go step by step and I think these next days will help me to increase my fitness level and to get in better shape".
Liverpool took the lead three minutes after Matip was replaced by Joseph Gomez during the International Champions Cup tie at the Bank of America Stadium in Charlotte, North Carolina, on Sunday.