JOHANNESBURG -- Never count out Oscar Pistorius.

The "Blade Runner" will be competing in the London Olympics in his favored 400 meters, after all.

The double-amputee runner from South Africa has spent almost all his life without lower legs and his entire track career proving he's good enough to compete with the best. He now has the chance to do just that.

The 25-year-old will be running in London in both the individual 400 and the 4x400 relay -- the first amputee track athlete to compete at any games.

"Today is truly one of the proudest days of my life," Pistorius said.

South African Oscar Pistorius will become the first amputee track athlete ever

to compete at the Olympics Joe Klamar/AFP/Getty Images

While his selection for the relay team was likely, it was only a surprise last-minute turnaround by South African sports officials on Wednesday that gave Pistorius the chance to run in his favorite event at the Olympics.

South Africa's Olympic committee and national track federation suddenly decided to clear Pistorius for the 400 at the London Games on his carbon fiber blades despite him just missing out on the country's strict qualifying criteria.

They added his name as the last on their team of 125 track and field athletes.

In London, Pistorius will easily be his country's biggest draw and will rival Jamaican sprinting sensation Usain Bolt and U.S. swimming great Michael Phelps for the world's attention.

Not bad for a kid who had both his legs amputated below the knee at 11 months old and originally didn't like track and field when he took it up as a teenager to rehabilitate from a rugby injury.

"To have been selected to represent Team South Africa at the London 2012 Olympic Games in the individual 400m and the 4x400m relay is a real honor and I am so pleased that years of hard work, determination and sacrifice have all come together," Pistorius said on Wednesday.

Set to realize his dream of competing at an Olympics and Paralympics in the same year, his joy also was obvious in a post on Twitter.

"Will be in @London2012 for both the Olympic and Paralympic Games!" the multiple Paralympic champion and soon-to-be Olympic athlete tweeted. "Thank you to everyone that has made me the athlete I am! God, family and friends, my competitors and supporters! You have all had a hand!"

Pistorius' Olympic selection wasn't clear cut. He forced his way in against all the odds as he's done time and time again.

Just like his last-gasp qualifying time to make history at the world championships last year, Pistorius claimed his place at the Olympics late. He also needed some help.

Pistorius ran a personal best 45.07 seconds last year and opened this season with a 45.20 -- both Olympic-qualifying times.

But he needed another 45.30 or better at an international meet before last Saturday to seal a spot in the 400, according to his national Olympic committee's regulations. He missed it by less than a quarter of a second in his final qualifying race at the African Championships.

"I have run two Olympic `A' standard times over the past 12 months and with the time I ran at the African Championships last week I know my speed and fitness are constantly improving so that I will peak in time for the Olympics," he said.

After he missed out on his second required Olympic qualifying time, the South African Olympic committee and Athletics South Africa appeared certain to overlook him in the 400. They had insisted throughout the season that they wouldn't relax their tough qualifying criteria for Pistorius.

But the late-season burst at the Africans, which also won him a silver and his first major individual medal in an able-bodied race, may have pushed officials to include him.

"Since he's going to be there (in London), our decision is he can run both," Olympic committee chief executive Tubby Reddy told The Associated Press. "There's no reason why he can't. Our decision is he can."

Pistorius has always maintained a place in the 400 final at the Olympics was his ultimate career goal, even before he had to take his case to sport's highest court to be allowed to compete against able-bodied athletes on his blades. Some still argue they give him an unfair advantage but he was cleared in 2008 and has never looked back.

"I have a phenomenal team behind me," said Pistorius, promising to put "everything" into his final preparations for London and what's likely to be his career pinnacle.

"I am aiming to race well, work well through the rounds, post good times and maybe even a personal best time on the biggest stage of them all. I am also hugely excited to then be competing to defend my three Paralympic titles at the Paralympic Games. I believe (we) will see some amazing times posted."

Controversy could still follow Pistorius at the Olympics if there's opposition to him running on his blades in any leg of the relay other than the first. Fears over the safety of other athletes, when runners bunch in the inside lane for the later legs, have been raised.

Pistorius' memories of his historic appearance at the 2011 worlds in Daegu, South Korea, aren't great, either.

He was dropped from the team for the final having helped South Africa through to the deciding race. He won a silver medal but was bitterly disappointed with the way he was treated there.

In London, though, he's sure to run both events. He's the country's only entrant in the 400 after his 45.20 and was picked alongside Willem de Beer, Ofentse Mogawane and Shaun de Jager for the relay team, which is ranked No. 2 in the world.

After finalizing its squad with the inclusion of Pistorius, the national Olympic committee said it had high hopes for all its athletes.

"As I have said many times before, we are not taking passengers to London," South African Olympic committee president Gideon Sam said.