Ayase Ueda's debut goal gave Lille a 1-0 away win at Toulouse in Ligue 1 on Thursday sending them provisionally top, three days after the Japanese international joined them.
In a game moved forward due to Lille hosting Real Betis in the Champions League on Tuesday, Ueda nodded home to break the deadlock on 73 minutes amidst a goalmouth scramble and against the run of play.
The 28-year-old scored 25 goals for Feyenoord in 31 games in the Dutch league last season before signing a deal with Lille on Monday.
Lille sold wonderkid Ayyoub Bouaddi to Manchester City for €100 million and Matias Fernandez-Pardo for a reported £51 million to Newcastle on deadline day.
Paired with veteran Olivier Giroud in the forward line, the €15-million recruit held his nerve in a lengthy scramble before Lille held on to take their tally to seven points from three games.
New Lille boss Davide Ancelotti got a winning start at Angers in their opening game before going two up at home to Paris Saint-Germain but ceding a draw as his side shipped two late PSG goals.
PSG can go back to the top on Friday when they play Monaco.
The northern French outfit will face Arsenal, Bayern Munich, Roma and Galatasaray, among others, in the Champions League this season.