Robertson – who was part of the Reds’ 20-man travelling squad – sustained a knock during the 3-1 win over Newcastle United at the weekend.
The left-back will therefore be assessed before a decision is made on his availability for the Group E tie at Stadio San Paolo.
“Robbo didn’t train today and we have to see,” Jürgen Klopp told Liverpoolfc.com on Monday.
“It is not a major thing, it was more precautionary today, but it is not 100 per cent sure [he will be available]. We will have to test it tomorrow and then we will see.