The Egyptian has been a revelation for the Reds this season and scored again against City to put his side in front just 12 minutes into the contest.
Alex Oxlade-Chamberlain followed up with a screamer of his own and Sadio Mane scored Liverpool's third as the club raced into a 3-0 half-time lead.
But, shortly after the break the club suffered a major injury hit, with Salah withdrawn from the contest with what looked to be a groin injury.
Salah was then replaced by Gini Wijnaldum and will now be a doubt for this weekend’s Merseyside derby and the second leg against City on April 10.
"I don’t know in the moment," manager Jurgen Klopp said of the sevarity of the injury. "He came to the sideline and said he sometimes feels something. That was enough for me to not even ask the doc how he is and [I] immediately took him off the pitch. After the game I asked him and he said: ‘I will be fine, I will be good’. But now we have to wait for the real diagnosis and not only Mo’s self-diagnosis. I don’t know in the moment."
Salah, who moved to Anfield from Roma last summer, has netted 38 times for Liverpool during his sterling debut season with the club.
Liverpool sit third in the Premier League, 18 points adrift of Pep Guardiola's runaway leaders but still 10 points clear of fifth-placed Chelsea, though the Blues hold a game in hand.