Hazard dazzled in his former side’s 4-1 demolition of Nancy in May 2012.
The Belgian had grabbed three in the first 30 minutes of the Ligue 1 clash.
And Mavuba, who still plays for Lille, has revealed the midfield maestro had gone boozing the night before with his move to Chelsea rubber stamped.
“Eden Hazard was drunk when he played his last game for Lille”
“We were certain to finish third and we were facing Nancy the following day,” Mavuba told reporters.
“It was Hazard’s last match with Lille and he wanted to organise a little something.
“We decided to go have a little drink. A little drink that dragged on somewhat. The following morning, Eden was still drunk.
“That evening against Nancy, not even with 30 minutes played, Eden had already bagged a hat-trick.
“The guy had not even slept, he drank for the entire night and he put away a hat-trick in 30 minutes.
“We all looked at each other [and] we told ourselves that this guy was the real deal.”