Cubelli was a significant part of the Brumbies squad during 2016, his first Super Rugby season. And earned high praise from coach Stephen Larkham, who described the Argentinean as the best running scrum-half in Brumbies history. Cubelli made his debut in round 1 of the 2016 season against the Hurricanes, scoring a try and helping the team to a 52–10 victory at GIO Stadium, Canberra. Cubelli's second try of the season came in round 11 against the Bulls of Pretoria. The Brumbies won 23–6 at home. Cubelli scored his third and final try of the 2016 season against Australian Super Rugby conference rivals, the Queensland Reds in round 15 at home once again, and put the scoreline to 34–17 and eventually help the Brumbies to win the match 43–24.