Pari gbolohun ti o tẹle: Agba ominira kan, Giroux ni a pe si ibudó ikẹkọ ti Gatineau Olympiques fun idanwo irin-ajo kan. Kò pẹ́ lẹ́yìn náà tí wọ́n fi gba iṣẹ́ lọ́wọ́ rẹ̀. Nigba akoko rookie rẹ pẹlu awọn Olympiques, Giroux gba awọn ibi-afẹde 39 fun apapọ awọn aaye 103 ni awọn ere 69 ati pe a pe ni Quebec Major Junior Hockey League (QMJHL) Rookie of the Year. Ó wọ inú
2006 NHL Entry Draft ati ti a ti yàn 22nd gbogbo nipa awọn Philadelphia Flyers. Awọn Flyers ṣe adehun Giroux si adehun ipele titẹsi ni Oṣu Keje ọjọ 23, Ọdun 2007.