Former Wallaby Nick Farr-Jones saves a wallaby on the Sydney Harbour Bridge

A wayward Wallaby making its way across the Sydney Harbour Bridge was helped by a former Wallaby on Tuesday morning. 

About 5am on Tuesday (local time) a wallaby decided to hop over the Sydney Harbour Bridge, also on the famous Australian bridge was former Wallabies captain Nick Farr-Jones, who decided to help out.

Farr-Jones, who made 63 rugby union appearances for Australia, said he was heading into work when he noticed the police on the bridge.

"It's unprecedented trying to grab a hold of a kangaroo on the Harbour Bridge," he said.

"[There was] a bit of chaos, but when you realised it was a wallaby it was really unusual."

The wallaby was eventually rounded up, and taken by mounted police to Taronga Zoo in a horse float.

"It was quite distressed, being held by two of the mounted police," said senior vet Dr Larry Vogelnest , who anaesthetised the adult male swamp wallaby before examining it thoroughly.

"Fortunately there didn't seem to be any significant injuries; it had some minor grazes on its face and its hind legs."

The macropod was given some medication and put on a drip, and staff at the Taronga Wildlife Hospital were monitoring it for signs of undiscovered injuries.

"These animals are quite susceptible to stress, and it causes muscle damage so I don't know whether that's happening," he said.

"Over the next 24 hours or so we'll get a good idea of whether there is any of those complications."

Story via stuff.co.nz