The Reds face their fourth clash of Group E on Wednesday night, with the Slovenian champions taking to Anfield looking for an unexpected result.
Liverpool produced a comprehensive performance away to Maribor last time out in the Champions League, with that 7-0 victory the biggest ever European away win by a British side.
And Klopp will be hoping for a similar display as the Reds look to book their place in the last 16.
Klopp suggested Lovren could still be involved if he joins his session on Wednesday morning, but this seems highly unlikely.
Therefore, two academy goalkeepers were drafted in, with Caoimhin Kelleher and Shamal George, reporting back from his loan spell with Carlisle United, joining the group.
Otherwise, Klopp will be able to call upon a strong squad, buoyed by their 3-0 victory over Huddersfield Town on Saturday afternoon.
Liverpool Squad at Melwood on Tuesday
Goalkeepers: Mignolet, Karius, Kelleher, George*
Defenders: Matip, Klavan, Gomez, Moreno, Alexander-Arnold, Robertson, Flanagan
Midfielders: Henderson, Can, Wijnaldum, Milner, Oxlade-Chamberlain, Grujic
Forwards: Firmino, Salah, Sturridge, Solanke, Ings*, Markovic*
(* Not in Champions League squad)