Shot putter Dylan Armstrong celebrates after winning a silver medal, the first of any kind by a Canadian in a throwing event at the world track and field championships. ((Andy Lyons/Getty Images))

With a massive fourth-round throw, Dylan Armstrong won Canada's only medal of the 13th IAAF world track and field championships on Friday in Daegu, South Korea.

Armstrong threw 21.64 metres to capture the men's shot put silver medal in an exciting and very intense competition.

Only 21-year-old David Storl of Germany could surpass the Canadian's mark, and he did that on his very last throw. The crowd erupted in a roar as the scoreboard showed he had reached 21.78m.

Armstrong had one last throw to change the colour of his medal but fouled on the attempt. Still, he was delighted with having won his first global medal.

"I am happy to get a medal for my country," he said. "And it's big for Athletics Canada as well because we haven't won a medal in any [throwing event at the world championships] before.

"It doesn't get closer than that, except Beijing [where he finished fourth by one centimetre]. This event is so deep anyone can win this.

"A big congratulations to David Storl. He's the future of shot putting for the next 10 years or more. But I'm really happy to get the silver medal. A medal is a medal. I'm happy to bring it home to Canada and to my community of Kamloops [B.C.]."

The result at once gives Armstrong great confidence in the buildup to the London Olympics. He has truly has been a model of consistency throughout the season, beating every major competitor on the European circuit. At the Canadian Championships in June he threw a Canadian record of 22.21m, which is still the longest throw in the world this year.

Finishing behind him in Friday's final were a host of Olympic and world championship medallists. Andrei Mikhnevich of Belarus claimed the bronze medal, and reigning Olympic champion Tomas Majewski of Poland and defending world champion Christian Cantwell of the United States were also in the field.

Storl surprised everyone by throwing a personal best of 21.50m in the qualifying round a day earlier, then took the lead in the sixth and final round of the final. Armstrong, the last thrower of the night, had about 90 seconds to respond.

"I was trying to stay focused and think about my last throw," said Armstrong. "I knew I had to bang one out on the last throw.

"It's a good setup for next year going into London. I'm going to try and get the gold there. I'm just going to keep my head down and going hard, and listen to my coach. He's the reason why I'm here today."

Asked if his coach, Dr Anotoliy Bondarchuk, will allow him a celebration before resuming training, Armstrong laughed.

"Yeah, right. I actually have got to train tomorrow morning at 9 o'clock," he said. "Like it or not, he's a warrior. Without him I wouldn't be here. I have about six more meets in Europe. I'm just going to bounce around and get the job done."

During the world championship competition, Armstrong was surprised when a young official crossed the track to point out somebody in the spectators' area who wanted to say hello. It was the shot putter's mother, Judy, and her sister Linda, who had flown over from Kamloops to surprise him.

Canada's poor showing thus far in the world championships, coupled with his world-leading performance, meant Armstrong was under pressure to bring home a medal, something he acknowledged.

"Definitely, I have taken the pressure pretty well this year and there has been a lot," he said. "It's growing and it's going to keep growing for the next year. But it's something I have just got to shut out and keep strong and keep going.

"The more successful you get in this sport, the more pressure there is. There are a lot of people who want you to do well."

Armstrong will fly to Zurich, where he's set to compete in the Diamond League meet there on Sept. 8. He currently leads the Diamond League season competition, and if he can retain that lead he will earn $40,000 US plus a diamond trophy worth approximately the same. Added to the $40,000 US second-place prize money in Daegu, and it's been a lucrative week for Armstrong.