Vic kayaker rescued from Port Melbourne

Three men have rescued a kayaker stranded at Port Melbourne.

The 56-year-old kayaker got into trouble near a rock wall between Webb Dock and Sandridge beach at about 6pm (AEDT) on Thursday.

He managed to flag down a passing boat after he became tangled with his leg rope and was having trouble keeping his head above water.

The two men on the boat kept the man's head above water until police arrived.

Sergeant Lachlan Holding from Water Police stripped down and dived into the water with a knife to cut the rope from the man.

The Broadmeadows man and one of his rescuers, a 55-year-old Meadow Heights man, were taken to St Vincent's hospital suffering hypothermia.

During the rescue the men's boat and the police boat drifted onto rocks and were both badly damaged.

Sergeant Holding said the kayaker was lucky and praised the two fishermen who risked their own safety and wrote off their boat to save his life.