The application relates to an adapter (78) for a syringe plunger (30). The adapter of some embodiments may include a first side (90) adapted to interface with a syringe plunger and an opposing a second side (92) adapted to interface with a drive ram of a medical fluid injector. The adapter may include a peripheral side surface (88) exhibiting a thickness and may include what may be characterized as at least one mating section adapted to engage with the syringe plunger. The mating section(s) may include a channel (93) extending through the entire thickness of the adapter. In some examples, the mating section(s) may include a stop (104) adjacent the channel that extends less than the entirety of the thickness of the adapter.