[1][2][3] Born and raised in the city of Christchurch in the South Island of New Zealand, Lentjes was educated at St Bede's College in his hometown where he won a Crusaders secondary schools title in 2008.
Injuries restricted him to just 6 appearances in 2015, but in that time he managed to score 5 tries which helped his side reach the Championship semi finals before they were well beaten by Wellington.
He was back to full fitness in 2016, featuring in 10 out of 12 matches for Otago during a season which saw them finish top of the championship standings - reaching the final before being defeated at home by North Harbour.
Following a string of injuries, Lentjes was called into the Highlanders squad midway through the 2015 Super Rugby season, making his debut in a 39–21 victory over the Stormers on March 28.
He remained with the squad for the rest of the season and played in both the semi-final win over the Waratahs and the 21–14 victory over the Hurricanes in the final as the Highlanders won their first Super Rugby title.