Liverpool duo Georginio Wijnaldum and Adam Lallana are facing a battle to be available for Monday night's game against Manchester United.
Wijnaldum picked up what was initially believed to be a hamstring injury whilst playing for his country earlier this week but tests by Liverpool since have indicated the player is suffering with a hip problem.
According to reports no return date has been given on how long his treatment will take.
Both Lucas Leiva and Emre Can are available to fill the gap if required.
Meanwhile Adam Lallana is not yet fully recovered from his groin injury that he sustained during the win over Swansea City almost two weeks ago.
His lack of training time will almost certainly rule him out of the game which is now just over 2 days away.
Klopp is a big believer that players must have completed enough training sessions before being eligible for games.
Both Wijnaldum and Lallana have been integral members of the LFC team so far this season, starting 8 and 7 games respectively for the reds across all 9 games in the League and cup.
Lallana has chipped in with 3 important Premier League goals too - the same number as Mane, Firmino and Coutinho in what has been an impressive attacking and mobile foursome.
Apart from a serious back problem at PSV during 2013-14 Wijnaldum has an excellent injury record. He has played more than 30 league games for his clubs in 7 of the last 8 seasons.
The reds take on Man United in the final game of this Premier League weekend - on Monday night at 8pm UK time.