Leuenberger represented Western Australia in the 2006 AFL Under 18 Championships and was rewarded with All-Australian selection as the ruckman.[1]
Leuenberger was drafted to the Brisbane Lions with their first selection and fourth overall in the 2006 national draft.[2] He made his debut against the West Coast Eagles in round 14, 2007 at Subiaco Oval.[3] His first two seasons saw him play 19 matches, and the first three of 2009 before sustaining a knee injury. He missed the remainder of the season after his knee became infected following surgery, and consequently lost 11 kilograms.[4]
Leuenberger played every match for 2010 and 22 in 2011, and amassed 724 hitouts during 2011, the second most in the league after finals.[5] During the 2012 pre-season, he suffered from tendonitis in his achilles, but was declared fit for the round one match against Melbourne,[6] however, he re-injured his achilles in round three against Fremantle,[7] which saw him miss the remainder of the season.[8]
Leuenberger missed the start of the 2013 season returning from injury, but was recalled to the senior side in round 2.[9] Despite persistent injuries, speculation arose that he would be a trade target as one of the "AFL's most wanted players,"[10] however, he re-signed with Brisbane in June, eliminating a potential trade at the end of the season.[11] He was named best-on-ground in the sixth QClash against Gold Coast and was awarded the Marcus Ashcroft Medal, after 20 disposals, 7 tackles, and 29-hitouts.[12]
Leuenberger played the first four games of the 2014 season before succumbing to another long-term injury, where he tore his meniscus and would miss at least three months.[13] After missing more than four months, he returned for the final round clash against Geelong at Simonds Stadium.[14]
The 2015 season saw Leuenberger as the backup ruckman to Stefan Martin[15] and he was predicted to leave Brisbane to a team where he would be the number one ruckman.[16] At seasons end, he decided to leave Brisbane through free agency and nominated Essendon as his club of choice.[17] He officially joined Essendon on 15 October.[18]
After playing 29 games for Essendon and 108 for the Brisbane Lions Leuenberger announced his immediate AFL retirement despite being offered a new contract for 2019.