At just 17, Fan was the youngest player on the professional tour in 2018–19. His first match was a 4–1 loss to Jack Lisowski in the Riga Masters, and his first win was against his practice partner Lyu Haotian 6–5 in the International Championship. However, he could only manage one further win in the remainder of the season, which finished in a 10–5 loss to Chris Wakelin in the World Championship.