The defender missed Tuesday morning’s training session at Melwood due to illness and subsequently was not among the 21 players who later departed John Lennon Airport for the quarter-final, second-leg tie.
Elsewhere, Adam Lallana has returned to the squad and Jordan Henderson has overcome an ankle knock; however, Alex Oxlade-Chamberlain remains on Merseyside to undergo additional fitness work after figuring for 45 minutes for the Reds’ U23s at Leicester City on Sunday.
Speaking to Liverpoolfc.com, Klopp said: “Dejan is ill. He had a bad night, the Doc was there and he had no chance to travel.