Liverpool manager Jurgen Klopp is debating whether to dip into the transfer market to sign a new centre-back.
The Reds lost both Dejan Lovren and Kolo Toure to muscles injuries in their win over Stoke on Tuesday, which could forced the German to act.
Lucas was forced to play the majority of the game in the heart of defence, as there were no centre-backs on the bench.
"In this moment with no centre-back fit I would say it is a situation where we have to think about going into the transfer market," he said.
"Two weeks ago we had three centre-backs, that's a good situation, at the start of the season we had five, now we have none.
"Injuries? Yeah that's it, we will look at our training! We don't train, we only recover, that is the situation now? There is no training.
"But it's no problem really. I am responsible for these things and if you want to make me responsible then it's okay.
"We have five hamstrings (Coutinho, Lovren, Martin Skrtel, Jordan Rossiter and Divock Origi plus Daniel Sturridge is still rehabilitating from one) and it's my responsibility, but it is like it is and we have to see what we can do."