Wang Zhen (right) and Cai Zelin celebrate after winning the men's 20-kilometer racewalking gold and silver medals, respectively, at the Rio Games, August 12, 2016. [Photo/VCG]

RIO DE JANEIRO - Wang Zhen claimed China's 12th gold medal of the Rio Olympics by winning the men's 20km race walk here on Friday.

The 24-year-old finished in one hour 19 minutes and 14 seconds, falling just 28 seconds short of the Olympic record set by his countryman Chen Ding at the London 2012 Games.

China's Cai Zelin took silver, 12 seconds behind Wang, with Australia's Dane Bird-Smith third in 1:19:37.

"I feel like I didn't have much of a plan about this race," Wang said. "I talked with my coach beforehand, but I just followed my heart. I picked up my pace with about three kilometres remaining, despite the fact my coach wanted me to wait until later."

Bird-Smith did not hide his delight at securing the bronze medal, and paid tribute Cai and Wang.

"I knew they were going to come out hard," he said. "I didn't know when it was going to happen, but as they went for it I thought, 'I got to get on their tails, and I got to go for it'.

"They took off with about 4km to go. They were the ones I was watching throughout the race. I wasn't going to let them slip away. Not without a fight. As soon as they went, they went hard. And they kicked hard.

"I probably wasn't expecting when they went. As soon as they hit it they went off like absolute rockets. I reeled them in and you know I was only a couple of seconds behind the whole way and I maintained that gap. I can't be happier with it."