The 20-year-old Brazilian is worried about the extent of the ankle injury sustained in PSG's victory at the weekend, an emotion mirrored by club coach Carlo Ancelotti
The Brazil international sustained the ankle injury following Thomas Mangani's tackle just before the hour mark in the win at the weekend, and the former Sao Paolo starlet attacked the nature of the challenge.
“It was a very dangerous tackle. I was very scared when it happened as it was the ankle I hurt in the first game against Valencia,” Lucas told reporters.
"It was a strong impact on my standing leg. I took the blow from behind and my leg got stuck.
"It hurts a lot on both sides of the ankle. I'm afraid of stepping firmly because I feel that it's a little fragile. I'm trying to step and walk, God willing it is nothing serious."
The 20-year-old was pictured on crutches hours after the match and was scheduled to undergo an MRI scan late on Sunday to discover the extent of the damage.
PSG coach Carlo Ancelotti added that he was concerned about his new signing, but did not know the seriousness of the injury.
"He must pass tests. Am I worried? Naturally I am," Ancelotti told reporters. "I hope he will recover soon, but I cannot say because I have not yet spoken to the doctor."