[6] Radford won gold at the 2006 Oceania Swimming Championships in the men's 10 km open water race.
On 31 August 2006 he placed 26th in the men's 10km race, at the 2006 FINA World Open Water Swimming Championships.
He was part of the New Zealand team at the 2011 World Aquatics Championships, where he came 27th in the men's 5km open water race.
Radford placed third in the men's 10 km open water race at the 2014 Pan Pacific Swimming Championships.
He again competed for New Zealand at the 2015 World Aquatics Championships, placing 30th in the men's 10km open water race.