Following these disappointments, Brown dedicated his 2018 season to focusing on the 2018 Commonwealth Games, to be held in Gold Coast. Named to Canada's team for the Games, specifically to compete in the 200 m, Brown initially placed third in the event final with a time of 20.34. However, second-place finisher Zharnel Hughes was then disqualified for jostling eventual gold medalist Jereem Richards, resulting in Brown winning the silver medal. This was the first major individual medal of Brown's senior career, which he credited with removing "that chip on my shoulder this year." He went on to enjoy success on the 2018 Diamond League, running the 200 mm in a sub-20 second time (19.98) for the first time at the Bislett Games in Oslo. He won the Golden Spike Ostrava over reigning World champion Ramil Guliyev.