The Egyptian collided with Magpies goalkeeper Martin Dubravka and was left prone on the St James’ Park turf.
Salah was conscious throughout but was clearly distressed while receiving treatment from Liverpool medical staff.
After a lengthy stoppage the winger was replaced by Divock Origi for the remainder of the match.
It does not look good for Salah’s involvement against Barcelona in the second leg of their Champions League semi-final clash against Barcelona on Tuesday.
Newcastle fans applauded Salah as he was taken off the pitch with his head in his hands.
Liverpool boss Jurgen Klopp showed his concern for the Egyptian on the sidelines as he was taken down the tunnel as well.
Reds legend Jamie Carragher explained how Salah had to go for the ball with Dubravka.
He said: “He had to go for it, and both he and the goalkeeper are brave going for it.
“It looks like he’s caught him with a hip.
“Obviously we saw what happened with Vertonghen so we know they will have to be careful.
“Liverpool are in such a precious situation in the title race now.
“This one is in the doctor’s hands, and rightly so.
“The right decision has to be made.”
Liverpool kept their title hopes alive at the death with Divock Origi nodding home in the 86th minute via the head of Jamaal Lascelles.
It had been hard work for the Reds as they were twice pegged back.
Virgil van Dijk gave Liverpool the lead before Christian Atsu equalised but then Salah stroked home to make it 2-1.
Salomon Rondon drove home to make it 2-2 before Origi’s deflected header found the back of the net to pile the pressure back on Manchester City.