The 33-year-old journalist blew kisses to the crowd as he walked final kilometre of the gruelling test of endurance before completing the course in three hours 40.58 minutes to win his first medal in his fourth Games.
Australia's Tallent crossed the line in second place for the third Games in a row, 18 seconds behind Toth, while Japan's Olympic debutant Hirooki Arai took bronze a further six seconds back. Tallent was awarded his London gold medal in a special ceremony in Melbourne earlier this year after Russian Sergey Kirdyapkin was stripped of the title for doping.