Family-focused Felix eyeing mother of all finales

DOHA - A warrior on and off the track, Allyson Felix is determined to exit the stage on her own terms as she sets out on the final leg of her glittering career at the world championships this week.

After 16 years at the pinnacle of her sport, the 33-year-old American has accumulated more world championship and Olympic honors than any track and field athlete in history.

In Doha, she will be aiming to add to an incredible collection of 25 medals, a dazzling haul that includes six Olympic golds and 11 world titles.