The Brazilian usually operates at midfield but had to fill in at centre-back against Ajax on Wednesday.
And after an excellent performance in the 1-0 win, Fabinho said he must continue to provide defensive cover for his injured teammate.
“Tactically, I have to be ready for the long balls and try to organise the team," he said. 'It's not easy but I have to do a little of what Virgil always does - talk to the team and try to be a leader.
“Of course I am not really but I will do my best. It was very important for me and for the team to keep the clean sheet today for confidence.
“The manager said to me I have to talk more to the team, to try to organise the team. Sometimes, a little bit I was like 'second ball', 'be ready' to try to press good. I try to be in this role as well, I try to do my best."