Mathieu Debuchy has been handed a new four-year contract by Lille.
LOSC have taken the decision to hand Debuchy a new deal, just days after he was sidelined for six months after damaging knee ligaments.
Debuchy, 20, is rated as one of Lille's best young prospects and the French Under-21 international did not hesitate in signing when offered fresh terms.
"I am very happy to prolong my contract with LOSC because I feel much at ease with the club," he said.
"I was in talks with the club for more than one month and the coach [Claude Puel] told me my injury didn't change anything.
"I will have surgery in one week at Strasbourg."
The club have also confirmed that 21-year-old Flavien Le Postollec has also signed his first contract with the club.
The midfielder only arrived in the summer from Martigues and although he has been limited to mainly reserve team duties - he has done enough to earn a two-year contract.