Unbeaten in all seven of her matches in Oamaru, Joyce, won all but one in straight sets. She was the second seed in the under-19 division and beat top seed Emma Cormack of Canterbury 3-1 in her final.
The Phil Drummond-coached Joyce was the top seed in the under-17 division and she beat second seed Anna O'Connor of Invercargill in the final. Joyce's Whangarei title was her first at North Island level and the top seed beat the second seeded Annmarie Holst of the host club 3-1 in the final.
"It was good to keep that North Island title in the Bay and the Eastern region as Rhiarne won it last year," left hander Joyce said referring to Hastings A2 grader Rhiarne Taiapa.
"These are the ideal results in my quest to make the New Zealand team for the 2019 Junior World Championships. If I can win the under-17 title at the national age group champs in Christchurch in October that would be another boost," Joyce said.
The Hastings Girls' High School year 12 student is expecting some tight matches particularly from Waikato's Anika Jackson who is in the New Zealand team which starts their Junior World Champs campaign in Tauranga tomorrow and didn't play in either of this month's island championships. Joyce was one of two Bay players to win titles in Whangarei.
Her Havelock North clubmate, B1 grader Jena Gregory, was also unbeaten on the way to winning the under-15 title. The second seed beat the top seeded Aucklander Natalie Sayes 3-1 in her final.
This was the second time right hander Gregory, 13, had played Sayes, an Australian Open age group champion last year, and the first time she had beaten her.
"It has to be the highlight of my four years in squash by far,' Gregory said.
The Joel Le Comte-coached Gregory has made rapid progress in the code. In 2015 she was a member of her club's E grade women's team which won their national teams champs in Masterton and last year she was in the Havelock North C grade team which finished second.
"That Whangarei title has made me more determined to win some national titles and make New Zealand teams in the future," Gregory said.
"Squash is my No 1 sport but I still play as a midcourter for my Havelock North High School's 9A netball team."
A shot player who ranked the cross court nick as her favourite weapon, Gregory, trains three times a week with her coach and at least six times on her own.
"I will stick to that routine because it works well. After my success in Whangarei I know I'm going to be among the hunted at the Christchurch nationals so I have to be ready," Gregory added.
Rosemary Mair of the Hawke's Bay club finished fourth in the under-19 girls section of the North Island champs and Joyce's sister and clubmate Rakairoa Joyce finished second in the under-13 division in Oamaru and third in Whangarei.
Gregory and Joyce will resume their regular training routines today and will play in the Hawke's Bay club's open tournament in Napier this weekend.