Vergier began racing for Lapierre Bikes as a junior in 2013. The following year he won both the Junior world cup overall as well as the Junior World Championships in Hafjell, Norway. In 2015, he moved up to the elite category and took third place at the UCI world cup round in Windham, U.S.
In 2016 the Lapierre team switched to specialized bikes. Vergier finished the UCI World Cup season in seventh place. His best result of the 2016 season was a second place in Leogang, Switzerland.