Kata switched to rugby league in 2013, signing with the New Zealand Warriors. Kata played for the Warriors Holden Cup team and was part of the side that lost the Grand Final 30–42 to the Penrith Panthers. Kata played in the 2014 Auckland Nines with the first grade side, before returning to the under 20s competition.
2014
Kata played for the Warriors in the inaugural NRL Auckland Nines At the end of the regular season, Kata played at centre in the 2014 Holden Cup grand final, scoring a hat-trick in the Junior Warriors' 34–32 victory over the Brisbane Broncos juniors. Kata won the Jack Gibson Medal as the grand final player of the match. On 20 October 2014 Kata made his international debut, playing for Tonga in their end-of-year test-match against Papua New Guinea.
2015
Kata again played in the Warriors NRL Auckland Nines team in 2015 and was named in the team of the tournament. In Round 1 of the 2015 NRL season, Kata made his first grade NRL debut for the New Zealand Warriors against the Newcastle Knightson the wing in the Warriors' 14–24 loss at Hunter Stadium. In Round 2, against the Canberra Raiders, Kata scored his first NRL career try in the Warriors' 18–6 win at Canberra Stadium. On 2 May 2015, Kata played for Tonga against Samoa in the Polynesian Cup, playing at centre and kicking 2 goals in Tonga's 16–18 loss at Cbus Super Stadium. Kata finished his debut year in the NRL with him playing in all of the Warriors 24 matches and being the top tryscorer with 12 tries in the 2015 NRL season, while mid-year his contract was extended until the end of 2018. On 8 September 2015, Kata was named in the New Zealand Kiwis' training squad. After not making the final New Zealand squad for the England tour, Kata played for Tonga in their Asia-Pacific Qualifier match against the Cook Islands for the 2017 Rugby League World Cup. He played at fullback, scored a try and kicked 4 goals in Tonga's 28–8 win at Campbelltown Stadium.
2016
In February, Kata played for the Warriors in the 2016 NRL Auckland Nines. On 7 May, he played for Tonga against Samoa in the 2016 Polynesian Cup, where he played at centre and kicked 1 goal. He made his New Zealand debut and played in the Four Nations for his adopted country. On 5 November, in the Kiwis second test against Australia, Kata scored his first try for the Kiwis in the 14-8 win at Ricoh Arena in Coventry. On 20 November, Kata played in the Kiwis 2016 Four nations Final match against Australia, playing at centre in the 34-8 loss at Anfield. Kata played in all 5 matches and scored 1 try in the tournament.
2017
In June 2017, Kata’s older brother Tevita died in Tonga and Kata would take a 3-week break from the game to return home to mourn with his family. Kata would return in Round 19 against the Penrith Panthers, scoring 2 tries, dedicated to his brother in the 34-22 loss at Mt Smart Stadium. Kata finished the 2017 NRL season with him playing in 19 matches and scoring 5 tries for the Warriors. On 4 October 2017, Kata was selected in the 24-man squad for Tonga for the 2017 Rugby League World Cup. Kata only played in 1 match for Tonga which was against Samoa, Kata played at centre but broke his foot during the 32-18 victory over their pacific rivals at Waikato Stadium.
2018
Kata made 23 appearances for the Warriors in 2018, as the club returned to the finals for the first time since 2011, scoring 12 tries in total. He scored a try in the historic first-ever Test match between Tonga and the Australian Kangaroos on 20 October 2018, played in front of a sold-out crowd at Mount Smart Stadium, Auckland.
2019
Kata was switched by the Warriors from left centre to right centre from the beginning of the season. After playing 6 matches and scoring 2 tries, with his form falling away he was dropped to their reserve team in the New South Wales Canterbury Cup. On 24 June it was announced that he had been granted an immediate release and had signed a contract with the Melbourne Storm until the end of the 2020 season.
