Police have arrested wanted suspect, Danny Rapley at a Kilburn address.
About 5.15pm on Sunday 21 March a member of the public attempted to intervene in an altercation between a man and a woman.
The member of the public was allegedly assaulted and the suspect left the scene on a blue Suzuki motorbike with the woman.
The victim, a 49-year-old man from Paralowie, was taken by helicopter to the Royal Adelaide Hospital where he remains in a critical condition.
The parties are not known to each other.
About 11.30am on Tuesday 23 March, officers arrested the wanted man without incident. He is expected to be charged later today.
Police are asking if anyone has any dashcam footage or CCTV of the incident to please contact Crime Stoppers on 1800 333 000 or online at www.crimestopperssa.com.au – you can remain anonymous.