Alex Oxlade-Chamberlain, Joe Gomez and Joel Matip are all now sidelined, while Emre Can and Adam Lallana have both struggled with injuries this season.
The Reds' No.11 fired Egypt to their first World Cup in 28 years when his late penalty sealed a 2-1 win over Congo in October, but now the Pharoahs are likely to head to the tournament without their talisman.
But Bayern Munich and Germany forward Muller thinks Salah could be the man to break up the Ronaldo-Messi era - if Liverpool beat Real Madrid in Kiev on Saturday.
Meanwhile, Real had its own injury scary just minutes after when right back Dani Carvajal left the game with a leg injury.
The 25-year-old was forced off with what looked a shoulder injury in the 31st minute of Saturday's final in Kiev.
When asked about Salah's World Cup chances and if the winger is a doubt, he replied, "Yes, he is".
Asked if Salah can star again for the Reds in the final, the 2005 Champions League victor told talkSPORT: "Yeah, definitely".
"It's about us as a team, we got here together as a team and we lose as a team".
"It's a serious injury, a really serious injury", Klopp told reporters. Prior to that, he has only played the African Cup final with Egypt against Cameroon, losing 2-1. "To have someone who scores and assists goals is a rarity".
Salah's performances this term, following his move from AS Roma, have made him Liverpool's top performer and a national hero.
Liverpool ace Mohamed Salah admits that he "feels great" to have been compared to Cristiano Ronaldo and Lionel Messi this season. He will now face a race against time to be fit for this summer's World Cup in Russian Federation.
In a heartbreaking scene even for non-Liverpool fans, tears ran down Salah's face as he left the match.