[3] Born in Oupeye and prior to turning professional, Delfosse also competed for the Pôle Continental Wallon–Bodysol–Euromillions team.

Having previously taken a podium finish at the 2012 Classic Loire Atlantique, Delfosse achieved his first two professional UCI victories within the space of a week, in May 2013.

[4] The following weekend, Delfosse won the 1.1-rated Rund um Köln in Cologne, after again featuring in the race breakaway.

Delfosse out-sprinted two other riders for the honours, beating Pieter Jacobs and Georg Preidler at the finish.

Following his retirement from the professional peloton, Delfosse became a salesman at a Decathlon sporting goods store in Verviers.