Joining ahead of the 2009–10 season, Naoupu made his debut for the side in a 2009–10 European Challenge Cup game with Worcester Warriors on 12 December 2009.

During his time at the club, the team finished fifth in the 2010–11 Top League, missing out on the title play-offs by one position, and were level on points with Suntory Sungoliath who came fourth.

[9] When he returned the Celtic League had been renamed the Pro12, and Connacht had qualified for the Heineken Cup, Europe's top club competition, for the first ever time.

[10] Naoupu made his first appearance at the top level of European rugby on 11 November 2011, when he started against Harlequins in Connacht's opening 2011–12 Heineken Cup game.

[5] In January 2013, it was announced that Naoupu had been offered a contract extension on the back of his good form, agreeing a deal to stay with Connacht until the end of the 2014–15 season.

[5] Naoupu suffered an injury in February 2014 however, which ruled him out for the rest of the season and he ended up making a total of 14 league appearances, with just six of these coming as starts.

Naoupu has also played for his country in rugby sevens, meaning he cannot qualify for Ireland through residency as he is committed to New Zealand under IRB regulations.