Decosta Gillen, a 15-year-old from Ballymena, won the National Boy/Girl 4 Championship in the 61kg category. She defeated Grace Fenlon of Paulstown with a 5-0 unanimous decision at the National Stadium in Dublin last weekend. Gillen boxes for Corpus Christi Boxing Club.

This victory makes her a two-time All-Ireland champion. She holds six Ulster titles and six County Antrim titles. Her wins include the Golden Girls Tournament in Sweden and the Cúchulainn International Box Cup. She has taken two Halloween Box Cup titles.

Gillen has competed in bouts in Italy. She trains several days a week with Corpus Christi Boxing Club in Belfast and other locations. She works with an elite squad aiming for the 2030 Commonwealth Games.

Upcoming events include a bout against Safiya Herish of Athena Select at the Beautiful Brawlers event on March 29 in Newark, England. She will compete in the Big Box Cup in Manchester in June and the Global Glove Development Box Cup.

In 2026, she plans trips with the County Antrim team to Cyprus and Spain. She has UK tournaments like the Manchester Box Cup and international bouts in the UK and United States scheduled, including in Las Vegas and San Francisco in October.

A spokesperson for Dunclug College stated pride in Gillen as a talented athlete representing the school.