NEW YORK • American sprinter Allyson Felix's pursuit of a rare 200m and 400m double at the Rio Olympics gained momentum on Monday when US officials asked the IAAF for a schedule change to make an attempt possible.

"We did receive an official request today from USATF," Paul Hardy, competitions director for the International Association of Athletics Federations (IAAF), said.

"This will be reviewed in the next few days."

Felix, the Olympic 200m gold medallist and world 400m champion, is seeking to become only the third female to complete the double in the Summer Games.

"Allyson is the most decorated female athlete in IAAF history and should have the chance to go for a double, competing in what likely will be her fourth and final Olympic Games," USA Track & Field (USATF) chief executive officer Max Siegel said in making the request.

"Such an achievement would elevate the sport at the Games, and as a federation, we owe it to her and to the sport as a whole to make the request," he added.

The current Rio Games schedule would make the double feat a daunting challenge.

Felix, winner of 20 Olympic and world championship medals, would need to compete in the first round of the 200m 75 minutes before the 400m final.

"Adjusting the schedule in my opinion does not hurt anybody," her coach, Bob Kersee, said.

Only twice has a female athlete won both at the Olympics.

Kersee-coached Valerie Brisco-Hooks claimed the honour in 1984 and France's Marie-Jose Perec won both in 1996.

The IAAF changed the schedule in 1996 so Perec and American Michael Johnson could attempt their double with the latter breaking the world record in the 200m and winning the 400m.

"All our training is towards her doing both," Kersee said.

"We are going to double at our Olympic trials and try and make the team in the 4 and the 2."

Felix, 30, has tried the 200m-400m double once on the global scene.

However, she could finish only second in the 400m and third in the 200m at the 2011 world championships in South Korea.

She had also wanted to attempt the double at this year's world championships in China.

But she decided in the end that the schedule would be too difficult.

Felix instead blazed to victory in the 400m final, with Dutch sprinter Dafne Schippers bagging the 200m in the fourth-fastest time ever.

The two, along with Jamaican Olympic silver medallist Shelly-Ann Fraser-Pryce, likely will clash again in one of the highlights of the Rio Olympics.

REUTERS