[4][1][a] Just like his fellow future internationals Émile Sartorius, Adrien Filez, André François, and Gabriel Hanot, Desrousseaux was introduced to football at the Lycée de Tourcoing [fr] by an English teacher, Achille Beltette (1864–1932), with whom he co-founded a non-school club, the US Tourquennoise, in May 1898, along with Albert Fromentin, one of the supervisors of the same high school.

[9] In the first and second leg matches of the 1900 Northern Championship final, Desrousseaux appeared as full-back, but since his brother Paul also played for the club at the time, it is not possible to confirm if that was Fernand.

[12] In the late 1900s, Desrousseaux was France's fourth or fifth choice behind the likes of Zacharie Baton, Maurice Tillette, André Renaux, and Henri Beau,[1] but despite this, he was able to earn one international cap during the 1908 Olympic Games in London, doing so as a member of the France B squad, conceding a total of nine goals in a resounding loss to Denmark in the quarter-finals;[2][3][4][13] his northern rival Tilliette would do worse with the A team, letting 17 goals go through in the semifinals.

[1][6] Likewise, during the half-time break of the match against Denmark, with France already 0–4 down, the English press noted, horrified, that he was smoking a cigarette on the sidelines.

[1] In April 1909, the L'Auto stated that he had "inaugurated a new kind of goal-keeping, by protecting his goal at the halfway line; it is an elegant, but dangerous way", which means that he usually played almost as a full-back, similar to the modern-day Sweeper-keeper.