Speaking to reporters on Thursday, Klopp confirmed that the trio would miss out in Exeter.
Coutinho and Lovren are likely to miss a lengthy period, having suffered hamstring injuries at the Britannia Stadium.
“Phil is more serious,” Klopp explained.
“The row is [that] Phil is more serious than Dejan, then Kolo, but none of these three players will be available for tomorrow.
“Kolo was a cramp, that’s not a problem, but after three days it’s not possible. For sure [he will be back] next week.
“With Dejan the situation is that he will be available after Man United [on January 17], and Phil needs one, maybe two weeks longer.
“With muscle injuries it’s really rare it’s quicker [than a few weeks].
“We’ll see how long it is.”
This leaves Klopp with little option but to heavily rotate his selection for the FA Cup, and he confirmed he would take this approach.
“We have to make changes,” he said.
“Of course we will make changes.”
The search continues, however, for further reinforcements.