A lifelong Crows fan, Milera’s childhood dream came true when he was selected by Adelaide with pick No.11 in the 2015 AFL National Draft. The classy half-forward previously made his SANFL debut for Central District as a 17-year-old while he played all six games for South Australia at the Under-18 National Championships. In 2017, he earned a NAB AFL Rising Star Nomination and took out the Mark Bickley Emerging Talent Award. In 2018, he excelled in a switch to half-back, including a career-high haul of 33 disposals against Gold Coast in Round Six. He continued his strong form into 2019, playing 17 senior games. A foot stress fracture meant he missed the majority of the 2020 season. Milera then unfortunately faced another injury-plagued season in 2021, before returning in 2022 to play 12 games. He enjoyed his most consistent campaign in 2023, averaging career-best numbers in average disposals (19.7), across 22 games. Unfortunately, Milera's 2024 campaign ended in Round Three after he ruptured the patella tendon in his right knee in the Good Friday match against Fremantle.