His first involvement with Canterbury's senior side came in 2014 when he played 4 times, twice from the start and twice as a replacement as the men from Christchurch reached the ITM Cup Premiership semi-finals before losing out to local rivals,. 2015 saw Canterbury back to winning ways, lifting the ITM Cuptitle after a narrow victory over. Despite facing a fierce battle for game time from fellow looseheads; Joe Moody and Alex Hodgman, Lienert-Brown asserted himself well and started 6 times during the season and also managed to net his first provincial try. With Moody spending the entire 2016 Mitre 10 Cup campaign with the All Blacks, Lienert-Brown saw his opportunities for playing time increase and he played in 10 of Canterbury's 12 games throughout a year which culminated in them winning the Mitre 10 Cup Premiership once more, this time with a comprehensive 43-27 win over Tasman which made it 8 provincial titles in 9 years for the red and blacks.
Super Rugby
Despite only being aged 21 and having no provincial experience under his belt, a front-row injury crisis for Christchurch-based Super Rugby franchise, the midway through the 2014 season saw him receive an unexpected call up. He was an unused substitute for the Crusaders home match against the on 28 April, but made his Super Rugby debut the following week as his side defeated the 28-7 in Johannesburg. He made 2 substitute appearances in total throughout the year, but was unable to secure a contract with any of New Zealand's 5 Super Rugby franchises for 2015, however, injuries once more provided him an opportunity and this time it was one he would take. He was called into the Dunedin-based squad early in the 2015 season and ended up playing 12 times in a fairytale season for them finished with them being crowned Super Rugby championsfor the first time after a 21-14 victory away to the in the final. A full squad member for 2016, he featured in 14 games and scored 2 tries as the men from Dunedin were eliminated by the at the semi-final stage. Tony Brown replaced the bound Jamie Joseph as the Highlanders head coach ahead of the 2017 Super Rugby season and he retained Lienert-Brown in the squad for his first campaign in charge.
International
Lienert-Brown was a member of the New Zealand Under 20 team which finished 4th in the 2013 IRB Junior World Championship in France. Not originally named in the squad, he was called up as an injury replacement for future Canterbury teammate, Alex Hodgman and went on to make 2 substitute appearances.
