Ka-yi is one of a group of Hong Kong players sitting in and around the top 50 in the world rankings and broke into the top 40 this year. After making her first appearance on the tour back in 2008, Ka-yi waited three years for her first win in the main draw of an event reaching the quarterfinals of the Crocodile Challenger Cup. Her first appearance in a final came in 2015, at the Contrex Challenger Cup. She lifted the title after defeating compatriot Ho Tze-lok in the final, earning her also the PSA Women’s Player of The Month Award after a surprise victory that saw her delight the local crowd to collect her first ever world tour title. The Hong Konger had to wait until 2019 for that elusive second title though, as she lifted the China Suqian International Classic trophy. The win, along with a first match win at a major tournament, as she reached the second round of the U.S. Open Championships, saw her break into the top 50 for the first time. At the trio of events in Hong Kong in early 2021 as players returned to the tour after suspension of tournaments brought by Covid-19, she made the quarterfinals of both the Chairman Cup and Hong Kong Football Club PSA, along with making it into the semis of the Chairman Cup 2. She had a strong start in 2022, reaching the semi-finals of the J.P Morgan Tournament of Champions Challenger before losing out to Kenzy Ayman after a five-game battle. Ka-yi then made it to the second round of the El Gouna International in Egypt, a platinum event, before stopped by Sarah-Jane Perry. Her second round defeat by world number one Nouran Gohar in the South Western Women’s Open in Houston prompt her world ranking to top 40.