At the 2017 World Cup, Luai was the only member of the Samoan squad without any prior NRL experience. He speculated on his selection, saying "I think you'll find Tyrone May was in the squad originally but due to his injury there was a spot for me."[2] Luai made his Test debut against Tonga on 4 November 2017.[9]
2018
Following an injury to Nathan Cleary, Luai was named to make his NRL debut off the interchange bench in round 4 of the 2018 NRL season.[10] However, he was cut from the line-up on gameday in favour of Wayde Egan, who was also on debut.[11] Luai made his NRL debut in round 10 against the Newcastle Knights, playing for 26 minutes off the interchange bench.[12] In round 17, Luai started at halfback in his second NRL match in the absence of Nathan Cleary and James Maloney due to State of Origin. His performance in the 36–4 win, which included two tries and multiple try assists, was heavily praised by the media.[13][14][15]
2019
Luai made 13 appearances for Penrith in the 2019 NRL season as the club finished 10th on the table and missed the finals for the first time in four years.[16] Luai also represented Samoa playing hooker in their 24-6 win over PNG. And played halfback in their 44-18 loss to Fiji.
2020
Luai had a breakout year for Penrith playing 23 games, scoring seven tries and bagging 23 try assists as Penrith claimed the Minor Premiership and reached the grand final against the Melbourne Storm, losing 26–20.[17] Luai's form throughout the season was rewarded with a spot in the New South WalesState of Origin 27 man squad although he did not play in the three game series.[18]
2021
On 30 May, he was selected by New South Wales for game 1 of the 2021 State of Origin series.[19]
Luai made his debut for New South Wales in game 1 where they defeated Queensland 50-6.[20] On 27 June, Luai was a part of the NSW side which defeated Queensland 26-0, sealing the series for 2021. However, Luai was ruled out of game three of the series after he suffered a knee injury in Penrith's round 16 win over the Parramatta Eels.[21]
Luai played all three State of Origin games as New South Wales lost the series 2-1.[24][25] During the series, Luai verbally abused an unconscious Selwyn Cobbo, whist standing over him. The move prompted criticism, especially after Luai refused to apologise.[26]
Luai won the 2022 Premiership with Penrith in a 28–12 win over Parramatta in the Grand Final. Following the grand final victory, Luai once again mocked the Parramatta club through social media posing for a photo with the caption "Daddy loves you". Luai had previously referred to Penrith as Parramatta's "Daddy" four days out from the match.[27][28]
On 6 October, Luai mocked Parramatta player Ryan Matterson on social media after Matterson had mentioned Luai had gone unpunished in the grand final for allegedly kicking Isaiah Papali'i whilst Matterson was suspended for three games over a crusher tackle on Dylan Edwards.[29][30] Luai posted the words "Cry 4 U" on Instagram accompanied by three crying emojis, and the chorus to R&B star Kennyon Brown’s song "Cry 4 You".[31] This was followed by an Instagram story posted after the game, which contained a racial slur "nigga".[32] The Panthers' management subsequently stated that the term was used affectionately, which drew further widespread criticism.[33]
On 18 February, Luai played in Penrith's 13-12 upset loss to St Helens RFC in the 2023 World Club Challenge.[37]
On 22 May, Luai was selected by New South Wales for game one of the 2023 State of Origin series[38] which was ultimately lost to the Queensland side. In game 2, Luai was sent off just before the end of the match for alleged fighting as New South Wales lost the match 32-6, and therefore the series.[39]
Following the game, Luai posted a message on his Instagram account which read “All you idiots have work tomorrow morning, We go again". Luai claimed it was in response to receiving death threats on social media following the match.[40]
On 3 July, it was announced that Luai had not been selected by New South Wales for game 3 of the series.[41]
In round 26, Luai was taken from the field early in the first half after suffering a suspected dislocated shoulder during Penrith's 32-18 shock loss to Parramatta.[42]
Luai played 22 matches for Penrith in the 2023 NRL season including the clubs 26-24 victory over Brisbane in the 2023 NRL Grand Final as Penrith won their third straight premiership.[43]
2024
On 3 January, Luai announced he signed a five-year deal with the Wests Tigers, commencing in 2025.[44]
On 26 May, Luai was selected by New South Wales ahead of the 2024 State of Origin series.[45]
Luai played in all three games as New South Wales won the series 2-1.[46]