A slotted guard for locking a needle in a shielded position as the needle is removed from a patient, and a guarded winged needle assembly including not only such a slotted, locking guard, but also a needle (with a winged hub attached thereto) slidably mounted within the guard. Preferably, the guard's slot has an angled portion so that when the hub and needle are fully retracted within the guard, the needle's tip will be oriented away from the slot. Also preferably, a piece of absorptive material is disposed in the guard to absorb any fluid dripping from the needle tip after the needle has been locked in its retracted position within the guard following an injection. An elongated anchor preferably protrudes outward from the guard so that the needle user may pull the wings of the hub (or a tube attached to the hub) in a conventional manner to retract the needle (and the hub and any tube attached to the needle) away from a patient while the user simultaneously presses the anchor member against the patient to hold the guard fixed. The user will press the anchor member (to hold the guard fixed) until the retracting needle's hub locks into its shielded position within the guard. In this way, the invention eliminates the risk of an accidental needle stick during and after the injection.