The Reds were required to register their ‘A’ list for the upcoming clashes with Paris Saint-Germain, Napoli and Red Star Belgrade by midnight on Monday.
This comes after Klopp’s squad for the Premier League was confirmed that evening, with Markovic omitted after the collapse of his deadline-day move to Anderlecht.
He seemingly has no chance of playing for Liverpool this season, having again been left out despite there being an opportunity to include him.
Klopp has registered just 21 senior players, with the manager restricted due to having no club-trained players and only being able to name four as association-trained.
Having seen the club’s attempts to sell him during the summer transfer window fail, Origi has been handed an olive branch with his inclusion.
But Alex Oxlade-Chamberlain misses out, with the midfielder having no chance of recovering from a serious knee injury to feature in the group stage.
Liverpool can, however, make three changes to the squad for the knockout stages, with the deadline set for midnight on February 1.
They will therefore be on the Reds’ ‘B’ list, which can include an unlimited numbers of players born on, or after, 1 January 1997 provided they have played for the club for at least two years.
Dominic Solanke is included in the ‘A’ list, however, ahead of his battle with Origi for the role of third choice.
Liverpool’s Champions League Group Stage Squad
Goalkeepers: Alisson, Mignolet
Defenders: Van Dijk, Lovren, Matip, Robertson, Clyne, Moreno
Midfielders: Keita, Fabinho, Wijnaldum, Milner, Henderson, Lallana
Forwards: Firmino, Salah, Mane, Shaqiri, Sturridge, Origi, Solanke
Notable U21: Alexander-Arnold, Brewster, Camacho, Chirivella, Gomez, Grabara, Jones, Kelleher, Phillips
Left out: Oxlade-Chamberlain, Markovic
Liverpool host Paris Saint-Germain in their first game of Group C on September 18, before a difficult trip to Napoli on October 3.