Mane sustained a hamstring injury on international duty with Senegal and faces up to six weeks on the sidelines.
Klopp admits Mane's injury has come as a blow to his side but the German manager is convinced Liverpool will cope without Mane.
Liverpool host Manchester United in the lunchtime kick off on Saturday and punters may be temped to use their free bet to back the Anfield outfit to pick up a result, as Klopp remains confident they can impress without Mane.
He told the club's official website: "Things like this happen. If you look around the world, a lot of players in this international break got injured.
"You always hope that nothing will happen, but as long as they are not around, we don’t know exactly what happens. It’s quite difficult to get in touch with all the different FAs and all that stuff like this.
"I had a chat immediately after the game with Sadio, how I always do with the boys. It was not clear it would be that serious, but he said ‘I feel something in my hamstring’, so it was clear it would be at least close for the United game - and now we know it’s much longer.
"That’s not cool, but we have to deal with it – how we always have to do."
When asked if he was confident other players would be ready to seize their opportunity, he replied: "Of course, they are all quality players, but it is not about talking about them; it’s all about really building a really strong side, a real strong line-up for the next game."