In Manchester City's case, the Premier League champions have carried numerous latter during their International Champions Cup tour in the United States, largely due to the fact that their stars are still recovering from a long 2017/18 PL season, in addition to duties at this summer's World Cup in Russian Federation.
The Senegal global came on at half-time at the MetLife Stadium and was a constant threat for the Reds.
Klopp praised Mane's performance after coming on in the second half.
Asked about Salah's return post-match, Liverpool manager Klopp told reporters: "I said before the game, it's not that he has problems - he has no problems".
"You saw the difference when Sadio came on".
Manchester City star David Silva has hinted that his current contract at the Etihad Stadium will "probably" be his last as he looks for "something different" in the future after giving the best years of his illustrious career to the club.
"With this and all the other changes, it changed the game".
Guardiola meanwhile said he was relieved no players were injured.
Nathaniel Phillips impressed onlooking supporters against Manchester City
"I grew up and am a more mature guy".
Of their first 15 games, seven are at home (where they recorded an unbeaten run last season) with only one of those seeing them play against a member of the Premier League's top six in Manchester City - at least six home wins is a realistic target.
"I learned that when I was little boy in Barcelona in the Academy".
"Of course he has all the talent to do that so we are happy for him to score, but he is still far away from his best condition".
"The speculation [over Real Madrid's interest in Salah] is what happens when you have good players". But we are going to adapt.
Salah and Mane both reported for duty for Liverpool in time for Wednesday's game.
After a goalless first half, City opened the scoring shortly after the break when Leroy Sane drove through the Liverpool defence before firing low in to the bottom corner for 1-0 in the 57th minute.
The game appeared to be heading for a draw until Tosin Adarabioyo crashed into Dominic Solanke in the area for a certain penalty.More news: Pompeo seeks to reassure lawmakers on Russian Federation amid bipartisan backlash
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