Sadio Mane scored a stoppage time penalty to seal a 2-1 win for Liverpool over Manchester City at MetLife Stadium in New Jersey.
Substitute Leroy Sane had put the Premier League champions ahead after 57 minutes, finishing neatly after bursting past Virgil van Dijk.
But late goals from Mohamed Salah, who has seemed to shrug off his shoulder injury from last season, and fellow forward Mane, were enough for Liverpool to claim the victory.
Speaking after the game, Liverpool boss Jurgen Klopp appeared indifferent about the game’s significance.
He said: “I’m pretty sure Pep [Guardiola] was a little bit angry because he doesn’t like, or he hates [losing], like I do.
“I was not a bit happy about the Dortmund game, even when there was a lot more good situations than today, especially in the first half. If you lose a game, you lose a game. How can you be happy? And if we win a game, that’s cool.
“That it was against Man City, we lost against Dortmund so what does that mean? We won against City, what does that mean? It’s pre-season, it’s really not important.
“The game for us was very important, but it is not a sign in the direction or whatever. It’s only a game we played and a lot of good moments which we can use and a lot of bad moments we can work on. That’s all.”