Water Police detectives are investigating after a male swimmer was hit by a jet ski at the St Kilda pier last week.
It is understood the male jet ski rider, along with his female passenger, collided with the swimmer underneath the pier on Wednesday, 26 February about 4.30pm.
The rider assisted the man out of the water and returned him to shore.
It is believed the swimmer sustained lower-leg injuries, and police are keen to speak to him about the incident.
The jet ski rider is believed to be of African or Middle Eastern appearance and aged in his late 20's or early 30's.
The jet ski is described as a current model, bright lime green Sea-Doo.
Investigators would like to speak to the injured swimmer, or anyone else who may have witnessed the incident.
Anyone who witnessed the incident or with information is urged to contact Crime Stoppers on 1800 333 000 or www.crimestoppersvic.com.au
