A blood collection assembly (10) includes a hub (12) with a distal end (14), a proximal end (16), a hub outer surface (18) and an internal opening (20) extending therethrough. The assembly (10) also includes a holder housing (22) defining a receiving chamber (24) and having a rearward end (26) adapted to receive a sample collection tube within the chamber (24) and a forward end (28) including a receiving port (30) extending into the chamber (24), where the receiving port (30) receives a portion of the proximal end (14) of the hub therein. An internal opening (20) of the hub (12) accommodates a puncturing element (32) at the proximal end (16) thereof for providing passage of a fluid therethrough, and the puncturing element (32) contacts the sample collection tube. The hub (12) and the holder housing (22) include an interengaging structure (54, 58) extending substantially perimetrically therearound for axially locking the hub (12) with the holder housing (22).
