The five-day meeting starts today at QEII Park in Christchurch and is the sole selection opportunity for July's Fina world championships in Rome.
Selection for the world championships would be a stepping stone towards next year's Commonwealth Games in New Delhi and lead on to the 2012 London Olympics.
Patience left his home in Wellington three years ago to join Andy Adair's Waves squad to advance his swimming career.
He finished third at the open championships in Auckland last year and is the dark horse to win the gold medal in Christchurch.
Patience (18), a student at the Sports Institute of Otago, is ranked third on this season's racing with a time of 15min 38.5sec, behind Matt Woodrow (Wellington) with 15min 32.47sec and Dylan Dunlop-Barrett (Taranaki) with 15min 33.45sec.
Patience won three gold medals in the grade for boys aged 17 and 18 at the New Zealand age-group championships in February in the 200m butterfly, 400m freestyle and 1500m freestyle.
He showed that he has the temperament for the big time when he finished sixth in the 1500m and eighth in the 800m freestyle at the world youth championships in Monterrey, Mexico, last July.
He made another significant advance in his swimming career when he erased Danyon Loader's name from the New Zealand record book by winning the gold medal in the 1500m freestyle at the national age-group championships last year.
Patience's gold-medal-winning time of 15min 45.35sec in the men aged 17 and 18 grade was 7.20sec faster than Loader's 1993 long-course time.
The qualifying level for the world championships is a step up from last year's Beijing Olympics as Swimming New Zealand strives to develop swimmers who can make finals at major international competitions.
Swimmers will have to reach 900 Fina points at the championships to make the team for Rome. This is the new Fina 900-point level that is equal to about 930 points under the old system that operated for the Olympics last year.
Accordingly, the team for Rome is likely to be smaller than the one for Beijing.
Katie Kenneally (Neptune), who won five medals - four gold and one silver - at the New Zealand age group championships at Wellington last month, has her best chance in the 200m breaststroke, where she is ranked second with a time of 2min 33.64sec.
She is ranked fifth in the 100m breaststroke with a time of 1min 11.87sec and sixth in the 200m individual medley with 2min 20.69sec.
Kenneally is a member of the Otago Swimming Coaching Academy (Osca) coached by Gennadiy Labara. Matthew Glassford (Neptune), who shifted to Dunedin from Alexandra nearly five years ago to improve his swimming, is another member of the Osca squad with medal prospects. He is ranked third in the 200m breaststroke with a time of 2min 20.80sec. He won a gold medal in the event at the national age-group championships.
Phoebe Williams' (Waves) best chance of a medal is in the women's 800m freestyle, where she is ranked fifth with a time of 9min 00.29sec.
Other swimmers with the chance of making the finals are Rhys Applegarth, Braden Doyle, Clive Cox and Rachael Hare, of the Waves club.
