Moreno was forced off the field midway through the Reds’ 7-0 win at home to Spartak Moscow in the Champions League on Wednesday night, heading down the tunnel with tears in his eyes.
Amid messages of support from his team-mates on social media Moreno began treatment on Thursday, as the club assessed the extent of his injury.
And speaking to Sky Sports on Friday morning, Klopp confirmed that Moreno would miss at least a week of action.
But as he elaborated, it seems more likely that the No. 18 could remain sidelined for the rest of the year, given Klopp’s uncertainty on his return.
“We need to have further assessment. I cannot say much about it,” he told reporters.
“It’s a very rare thing. So far the specialists aren’t sure [how long he’ll be out for].
“Not Everton, but if it’s in a week or so or a little bit longer we have to wait for that. There’s a little damage around the tendons.”
Moreno has been in excellent form so far this campaign, reclaiming his role as Klopp’s first-choice left-back to make 20 starting appearances.
Sunday will likely see Klopp keep faith in Milner, given his suggestion that derby experience is vital, but Robertson may well be given an opportunity at Anfield in midweek.
The Scotland international has made just four outings for Liverpool so far, but has produced some encouraging displays on the left flank.
An away clash with a West Brom side under new management in Alan Pardew could be the perfect time to give Robertson a chance before Moreno makes his recovery.