The 49-year-old played for four years at PSG between 1991 and 1995 and won the Ligue 1 title in 1993-94
"I like Lucas a lot, he works so much when the team defends," he told beIN Sport. "Then when he attacks he's just unstoppable. He's too quick! He's intelligent too and changes direction so easily. And what's more, he's young.
"Thiago Silva is a great man. Brazil are lucky to have him because when he plays the team defends so easily, but when he's not there we have a lot of problems."
PSG are currently four points clear at the top of the Ligue 1 table.