Matthew holds the European Record for the 400m which he broke during the 2023 World Championships where he won the silver medal. In 2022, Matthew won gold in the 400m and 4x400m at the European Championships, silver in the 400m at the Commonwealth Games and bronze in the 400m at the World Championships. He was also European 400m Champion in 2018 and silver medalist in 2014. Matthew qualified for the final of the 400m at the 2016 Olympic Games in Rio and was part of the winning 4x400m team at the 2014 Commonwealth Games and bronze medal wining team at the 2017 World Championships.