Abstract: A blood collection assembly for use with a blood collection container which includes a cannula-penetrable closure with a lip element associated therewith. Included in this assembly is a receptacle having a closed end and an open end for the receipt of the blood collection container, and a peripheral surface between the ends. A cannula extends from the closed end into the receptacle and also extends outwardly from the closed end of the receptacle. A spring-resilient valve sheath may cover the inwardly extending cannula for control of fluid through the cannula. A spring-depressible tongue is connected to the peripheral surface of the receptacle and is inwardly depressible for engaging the lip element on the blood collection container to prevent outward movement of the container during the blood collecting procedure.