Abstract: A blood specimen collecting system utilizes a disposable needle assembly and standard blood collection and receiving tubes of the type sealed by a pierceable septum. The system includes a hollow cylindrical support adapted to receive a blood collection tube through a rear end thereof and support the needle assembly at a front end thereof. A needle support and ejection mechanism includes a pivotable lever assembly having first and second retainer bracket arms designed to cooperatively engage opposing surfaces of a needle assembly base. The lever assembly is pivotally biased to a first position wherein the first retainer bracket arm applies force to the needle assembly base to bias the needle assembly rearwardly into a small aperture of the cylindrical support.