Lens sporting director Antoine Sibierski has confirmed the interest of Chelsea in Thorgan Hazard.
The youngster is the kid brother of new Chelsea signing of Eden Hazard.
"I've since learned that Chelsea are interested in his possible arrival," Sibierski told La Voix du Nord newspaper of Thorgan.
"I can understand why a player would want to leave Ligue 2 to go to Chelsea. We're in discussions.
"Now, like in every transfer with a year left on his contract, it must be paid for. There are also compensation fees for training him."