Spokesman Neville Hopkins said the turnout is slightly higher than 2016, with players coming from Wellington, Hawkes Bay, Taranaki and Manawatu.
"Play starts at 8.30am each day and we may have to use lighted courts to complete play on any day, as there are over 300 matches scheduled - more than 50 more than last year because of the extra entries in the Open grade."
The back-up artificial grass options are at the Whanganui High and Whanganui Intermediate schools if Bassett Street's six plexipave hard courts are affected by rain.
New Wanganui Tennis Club head coach Leela Beattie is tournament director, being assisted by a number of junior committee members, while a NZ Tennis Umpire Association official will be present - which is a requirement for Tier 3 events like this now.
"All the draws and court allocations are done by a computer programme, which makes the job of scheduling courts and players much easier than in the old manual days," said Hopkins.
Seedings for the Monday tournaments won't be confirmed until the completion of the 10 and 14 year grades, although as par for the course it is the visitors who will dominate, as Beattie begins the task of rebuilding the local scene after the departure of several stars.
The 14 year divisions are the largest with both 32 boys and girls.
Top girls seed is Nikayla Barnard, currently ranked 190th in New Zealand and the clear favourite, as she is 66 spots ahead of second seed Claire Brownlie.
The discrepancy is even larger in the boys draw as Henri Lyons will have to have a bad weekend if he is not to win the title - given he is a whopping 350 spots ahead of second seed Shane Colton.
Both Lyons's father and his brother are also competing this weekend.
There are five boys in the 10 year grade and six girls.
The top seeds are Travis Christison and Ayla Giesen respectively.
Among the Open grade competitors are some noteworthy names.
Jaden Grinter, once ranked as high as 71st on the ITF Junior Men's world circuit, will be playing in the Open doubles with Michael McGlinchy.
Marc Paulik is ranked 26th in New Zealand and will also play the Open doubles with one of the boys he coaches.
In total there are 28 players in the Men's Open, and five in the Women.
Jakim Malan and Hannah Sutherland-Smith are the top seeds.
The club is also pleased the St Johns Club came on board as the major sponsor after the Slazenger sponsorship of the previous five years expired. Raceway Motels are also assisting sponsorship this year.