Runner Allyson Felix poses for a portrait with the US flag at the US Olympic Committee Media Summit in Beverly Hills, Los Angeles, California, March 7, 2016.[Photo/Agencies]

Already America's most decorated female sprinter, Allyson Felix launches the most difficult challenge of her career this week.

Despite an ankle sprain that pains her when she runs, the 13-times global champion hopes the July 1-10 US Olympic trials bring her a double ticket to Rio where she hopes to become the third woman to win a 200-400 meters double at the same Olympics.

"It was going to take a whole lot not to get me here," Felix told a news conference on Wednesday.

A freakish weightlifting accident in April produced significant tears in multiple ligaments of her right ankle.

Yet her Rio goal never died, just the means of getting there, with pool workouts and therapy supplanting track sessions for nearly a month.

Now the double gold dream she has nurtured for over a decade will depend on a top-three finish in both the 200 and 400 meters at the trials.

"If I get first, second or third I will be just as happy," said the 30-year-old Californian, who is the Olympic 200m gold medalist and world 400m champion.