A product of Timaru Boys High School, Seiuli made his debut for the Highlanders in May 2016 and helped his side reach the Super Rugby semi-finals. He was part of the Highlanders side which beat the British and Irish Lions in 2017, alongside current Warrior Siua Halanukonuka.
Since 2012, the New Zealander has represented Otago 60 times in the Mitre 10 Cup and NPC.
Having missed the 2019 Super Rugby season due to an ACL injury, Seiuli returned to action for Otago in August and has played five times so far this season.
He will join the Warriors following Otago's 2019 ITM Cup campaign.