Jurgen Klopp's plans for Saturday's huge visit of Manchester United were dealt a major blow after Mane picked up a hamstring injury while on Senegal duty.
Mane, who was Liverpool’s Player of the Year last season, is now set to be out for up to six weeks.
The pacy forward scored in his first three Premier League matches this term before being sent off at Manchester City.
His absence, which will see him miss matches against top-four rivals United, Tottenham and Chelsea, will still be keenly felt at Anfield at the weekend.
Salah, who found out about Mane’s blow via a text conversation between the two, has called upon Liverpool to focus on beating United despite losing one of their key stars.
The Egyptian said: "I texted him when he was at the national (team) and then when he came back. He told me then he was injured, so that's bad news for everyone.
"But that's football and anything can happen. Now we have to focus on the game and keep moving forward."
Meanwhile, United great Gary Neville believes Liverpool have been dealt a ‘big psychological blow’ following Mane’s injury.
He told Sky Sports: “Sadio Mane has become such a force for Liverpool.
“He's definitely the attacker who offers something different for Liverpool, but they have still got Mohamed Salah, Roberto Firmino and Philippe Coutinho so they do offer a real threat.
“You would have never said before Mane joined he'd be the most pivotal player but you would now say, given what happened during the African Cup of Nations last season, losing him is a big psychological blow.
“However, they do have Salah, who does fill that speed gap and gives them something else, so that ultimately means the loss is less of an issue this time.”
