Brun played college golf at Texas Christian University.

[2] In September 2012, Brun won the Allianz Golf Open Toulouse Metropole on the Challenge Tour.

[3] In 2015, Brun medaled at one of the qualifying school events for the PGA Tour Canada.

[8] He was also twice runner-up during the season and finished second in the Order of Merit to gain a place on the Challenge Tour for 2021.

[10] Three weeks later he won the Open de Bretagne, his first on the Challenge Tour as a professional, two ahead of Chase Hanna and Jérôme Lando-Casanova.