Northern Wanganui, coached by Nicole Dryden, consists of players from Ruapehu, Waiouru, Taihape and Kaiwhaiki.
With Angel Hamahona at the helm, the Southern Wanganui team consists of players from Rangitikei, Ratana and the eastern and southern ends of town.
Metro will be players from the central city and is coached by Marjory Keelty.
"The above coaches have been watching premier and senior netball over the last few weeks and have selected players to trial for the teams," said Murphy.
" The theory behind this [tournament] is to create competition, fair play and relationships within the greater Wanganui union."
It will officially be called the Vanda Buttars Memorial in memory of the stalwart player, coach and administrator who passed away last year.
Among Buttars' many coaching successes was guiding the Wanganui senior team from 1991-97, during which they won the second grade at the nationals in 1995 and played in first grade as one of New Zealand's top eight provincial teams in 1996-97.
"She was an amazing lady who touched a lot of hearts in the netball community throughout the region and I am sure she would be very proud to have this named after her," said Murphy, who was one of Buttars' many proteges.
Game times at Seddon Gym are Metropolitan v Southern at 9.30am, Metropolitan v Northern 12.15pm, then Northern v Southern at 3pm.