Hamel, who made his Champions League debut as fourth official for Celtic’s 5-1 loss to Real Madrid at the Bernabeu on November 2, was just 42-years-old. He was most recently on VAR duty for Paris Saint-Germain's win over Auxerre at the Parc des Princes on Sunday.
One of France’s most respected referees, he took charge of 135 Ligue 1 fixtures and 85 games in the second tier. He has also officiated during a number of international and European matches. Hamel passsed away on Tuesday evening after suffering a stroke during routine training exercises.
A statement from the Union of Elite Football Referees (SAFE) read: "Arbitration is in mourning. We learn of the death of our Colleague and Friend, Johan Hamel, Ligue 1 referee, at the age of 42.
"To his Family, Relatives and Friends, the SAFE and the Arbitrators send their deepest condolences. Johan, we will miss you."