Trbojevic has played at representative level for the Prime Minister's XIII and New South Wales in the State of Origin series.

[14] In Round 20 against the New Zealand Warriors, Trbojevic scored his first NRL career try in the club's 32–12 win at Mt Smart Stadium.

[15] On 8 September, Trbojevic's form for Manly, which finished the season in 9th place with an 11–13 record (missing the finals for the first time since 2004) saw him win the clubs "Roy Bull Best & Fairest" award for the year.

[16] On 26 September, Trbojevic earned his first senior representative jumper when he played at prop for the Prime Minister's XIII against Papua New Guinea in the 40–12 win in Port Moresby.

[20] After again playing for the Prime Ministers XIII, on 13 October 2016, Trbojevic was called into the Australian Kangaroos squad for the 2016 Rugby League Four Nations tournament after Canberra Raiders forward Josh Papalii withdrew with an ankle injury.

[23] He was a shining light (alongside his younger brother and star fullback Tom Trbojevic) in an otherwise rocky season at the Manly-Warringah Sea Eagles.

Trbojevic was selected by New South Wales to play in the 2019 State of Origin series after a good start to the season.

[24][25] Trbojevic made 25 appearances for Manly in the 2019 NRL season as the club qualified for the finals after finishing in sixth place.

He played in all three games as New South Wales suffered a shock 2–1 series loss against an under strength Queensland side.

[31] He played 23 games for Manly in the 2021 NRL season including the club's preliminary final loss against South Sydney.

Trbojevic played 18 matches for Manly in the 2023 NRL season as the club finished 12th on the table and missed the finals.