Katoa made his NRL debut in round 1 of the 2020 NRL season for the New Zealand Warriors against Newcastle Knights starting from the bench, in the club's 20–0 loss.[2][5] He had only played 13 games of rugby league in his life before making his debut.[3]
Katoa scored his first try in the Warriors' 18–0 win over the St. George Illawarra Dragons in round 3 of the 2020 season. Katoa was one of a few Warriors players who were initially not allowed to travel back to New Zealand during the height of the COVID-19 pandemic in 2020.[6][7]
He was released from his Warriors contract in 2022 to join the Melbourne Storm in 2023 on a two-year contract.[8][9][10][11]
After impressing during the 2023 NRL preseason challenge,[12] Katoa made his Melbourne Storm debut against the Parramatta Eels in round 1 of the 2023 NRL season, and was presented with his debut jersey (cap 226).[4] He would play his 50th NRL match in round 4 of the 2023 season. Katoa played 21 games for Melbourne in the 2023 NRL season as the club finished third on the table. Katoa played in Melbourne's preliminary final loss against Penrith.[13]