After conceding the penalty which gifted Wigan a point at the JJB Stadium, the 22-year old was sent off for two bookable offences against Everton in midweek, ruling him out of today's trip to Portsmouth.
Despite enduring a torrid few days in his Anfield career, Lucas retains the full backing of his manager.
"We will miss him. We have some problems and he is a player who could have been really important for us," said Benitez.
"I can't speak for every single fan, but every member of staff knows he is a very good player and his teammates know he is a good player.
"Against Wigan, for me, Lucas was the best player on the pitch. Then the other day at Everton he was also playing well and the ref made three mistakes. He gave one foul against him which wasn't, showed one yellow card which was wrong - and then the second yellow could be, but the player went over easily.
"I will support Lucas 100 per cent, always. He is a fantastic player, he is a nice boy and a very good professional. He has quality, he is learning and is improving all the time.
"It is not difficult for me to say that I support him 100 per cent."