After a tough rookie season, Miller took a stunning maiden win in 2016 at the TT Circuit Assen, despite a season that began with a broken leg and was subsequently interrupted by more injury. Taking a good number of top-ten results, Miller remained with the Estrella Galicia 0,0 Marc VDS team for 2017 and impressed once more before moving to Pramac for 2018, switching from Honda to Ducati machinery.

More consistent and taking his first pole position, it was a solid season for the Australian, who remained with Pramac Racing in 2019. Miller was super impressive: five podiums came the number 43's way that year, and he continued to show his class throughout 2020, earning another four podium finishes, but no victories. A move to the factory Ducati squad in 2021 delivered two victories, three further podiums, and fourth in the World Championship. Miller again proved his quality in 2022 with seven podiums, including the best MotoGPÔ performance of his career when he won with ease in Japan.

After five years in red, Miller donned the orange of KTM, claiming a double podium at the Spanish GP in 2023 and another Sprint podium at the German GP.

Miller is now up for a new challenge and has decided that in 2025 he will be rejoining the Pramac set-up, this time as a Factory Yamaha rider.

In 2025, Miller returned to Pramac, reuniting with the team he previously raced with from 2018 to 2020, this time equipped with a factory‑spec 2025 Yamaha YZR‑M1 and full Yamaha support. Overall, it was a tricky season. His strongest performance of the season came at the Grand Prix of the Americas, where he delivered a standout fifth‑place finish. Looking ahead to 2026, Miller remains committed to building on Yamaha's developing M1 project as he continues adapting to the evolving package and strengthening the team's competitiveness in the premier class.