How long does it take to change a life? For a Uruguayan runner, just 42.195km

Only sport can in a single moment rewrite the trajectory of a career, emotionally drain a coach, and turn an athlete from anonymous competitor to international headline.

- Rohit Brijnath Assistant Sports Editor

How long does it take to change a life?

0.06 of a second?

Which is the margin by which Frenchman Jimmy Gressier wins the 10,000m after a storming finish.

Or 0.03 of a second?

Which is what happens in the men's marathon, where after two-plus hours of running two men hit the tape at the same time. So the winner is decided by a photo finish.

Or two hours, 27 minutes and 23 seconds?

Which is the marathon finishing time achieved by an unheralded young woman from Uruguay, a timing so profound that it leaves a young man from Flagstaff, Arizona in tears on a bus in Tokyo.

Only sport does this every day.

Only sport can in a single moment rewrite the trajectory of a career, emotionally drain a coach, and turn an athlete from anonymous competitor to international headline.

The runner from Uruguay, a country without a single world athletics championship medal, is Julia Paternain. The coach from Flagstaff is Jack Polerecky, 29, who sets a series of goals with her before the race.

"Our 'C' goal was top half of the field," he tells The Straits Times from Tokyo. "Our 'B' goal was top 20. Our 'A' goal was top eight. Top three was not even in our conversation."