Question: Who was the first winner of the award  that awards the player aged 23 years or under at the start of the season whose performances are considered to be the best, playing in Ligue whos current holder is  a French professional footballer who plays as a forward for Spanish club FC Barcelona? 
Sentence (from "Ligue 1 Young player of the year"): The current holder is Ousmane Dembélé, who won the award for his performances throughout the 2015–16 campaign for Rennes scoring 12 goals and assisting 5.
Relevant evidence: No