Finley is a two-time British champion and has also medalled at various World Triathlon events including a silver medal at World Triathlon Para Series Montreal.
He started out in athletics having been talent spotted at a Parasports Day held by England Athletics. He later added swimming and cycling to his training as he became involved in paratriathlon. His debut season saw him finish third at the British Championships in 2017 before he went one better a year later and won a silver medal. His international paratriathlon debut also came in 2018 as he finished eighth at Funchal Paratriathlon World Cup.
In 2019 he finished sixth at Alanya Paratriathlon World Cup before he followed it up with a sixth place at 2021 World Triathlon Para Cup A Coruna. He then came fifth at the European Championships. His first international paratriathlon medal came later that year as he won gold at World Triathlon Para Cup Alhandra. He was off the podium for the remainder of the year but returned to it in 2022 as he came second at World Triathlon Para Series Montreal before becoming British Champion for the first time just eight days later.
He secured another British title in 2023 before ending the season with three straight podium finishes as he came second at World Triathlon Para Cup Taranto and third at both World Triathlon Para Cup Alhandra and Malaga.