The 19-year-old claimed the title by just seven centimetres from Ukraine's Oleksandr Pyatnytsya, who had to settle for silver.
Walcott's second-round throw of 84.58m proved good enough for victory, with Pyatnytsya throwing 84.51m in the third round.
Finland's Antti Ruuskanen claimed the bronze medal with a throw of 84.12m in the fifth round.
Related content
- Athletes
- Sports
- Countries
