Masson was the IBO World Crusierweight champion after his win over Italian boxer Fabio Turchi in April 2023.
Although unable to pick up a New Zealand national title, after moving to Australia and joining a new gym he managed to win Australian Golden Gloves.
After a win over Abdullad Saad Alghmadi in October 2018, Masson fought in New Zealand in November 2018 for the first time since fighting as an amateur boxer.
[5] Masson took on Tuvalu born New Zealand boxer Navosa Loata on the Lucas Browne vs Junior Pati undercard.
[6] After a win over New Zealander Waikato Falefehi, Masson fought journeyman Roger Izonritei.
[9][10][11] Masson finished his 2019 boxing year in October with a unanimous decision win over Indian boxer Kuldeep Singh.
Masson had his first and only fight of 2020 in March against New Zealander and IBO Asia Pacific champion Lance Bryant.
In February 2021, Masson announced that he would move to Brisbane, Queensland, Australia to focus on his boxing career.
[26] In January 2023, it was announced that Masson would take on Italian boxer Fabio Turchi on April 1 for the vacant IBO World Cruiserweight title.