Coutinho is not a direct replacement for Mane as he plays in a more central position, but Klopp may look to introduce him in tomorrow night's Champions League game against Sevilla, even if he is used from the bench to start with.
After a 6-3 aggregate victory over Hoffenheim in their play-off qualifier, Liverpool will head into the Champions League confident of improving on their showing from three years ago.
The wantaway Brazilian is yet to feature in a competitive match for the Reds this season after being denied a move to Barcelona despite submitting a transfer request.
Midfield: Klopp may decide to play two in central midfield with Emre Can dropping in alongside skipper Jordan Henderson to help counter the attacking threat of a risky Sevilla side.
"Phil is a fantastic player, and hopefully we can use him as quickly as possible".
Alongside Sevilla, Liverpool have also been grouped with Spartak Moscow and Maribor for their Champions League campaign. All those opponents are beatable and they should have additional motivation to win this first game against Sevilla at Anfield.
Liverpool will host Burnley at Anfield in their league match on Saturday.
The Brazil midfielder, who was the subject of multiple bids from Barcelona this summer, was not considered for Saturday's 5-0 defeat at Manchester City after being told to work on his fitness by manager Jurgen Klopp.
'I could [give you an idea], but I'm sure all the Liverpool supporters around the world are ready to wait another 24 hours, ' Klopp said.
I fancy them to get the win that will send them on their way in the Champions League, but they can not afford a second defeat in succession as it would halt their early season momentum in an instant.