Cika wannan jumla: "Colonado Avalanche ta zana shi a matsayin na 45 a cikin jerin"
1999 NHL Entry Draft, Grenier ya yi ciniki zuwa Boston Bruins tare da Brian Rolston, Samuel Pahlsson da kuma zagaye na 2000 na zagaye na 1 don Ray Bourque da Dave Andreychuk a ranar 6 ga Maris, 2000. Ba a sanya hannu ta Boston ba, Grenier ya sanya hannu tare da Phoenix Coyotes kafin kakar wasa ta 2001-02. Tun lokacin da ya fara aikinsa, ya yi amfani da mafi yawan lokacinsa a AHL tare da 'yan kira zuwa NHL tare da Coyotes, Vancouver Canucks, da Philadelphia Flyers.