[3] On 26 December 1897, the 15-year-old Grandjean started in the very first football match in the history of the Parc des Princes as a last-minute replacement for Maurice Macaire; Club Français was defeated 1–3 by the English Ramblers.

[5] In the following week, on 3 April, he started in the final of the 1898 USFSA Football Championship against Standard AC at Courbevoie, assisting Gaston Peltier's opening goal in an eventual 2–3 loss.

[6] In the following year, on 16 April 1899, he started in the play-off match against Standard AC to decide the 1898–99 USFSA Paris championship [fr], which ended in a 3–2 win.

[9] Together with Lucien Huteau, Georges Garnier, and Gaston Peltier, Grandjean was a member of the Club Français team that won the 1899–1900 USFSA Paris championship.

[13] Grandjean played for the AS Française in the 1905–06 and the 1907–08 seasons,[14][15] winning the Coupe Manier in 1908, which that year was awarded to the team composed of at least eight French players with the highest ranking in the USFSA Paris championship [fr].