American teenager Madison Keys said a new set of headphones for her portable media player was on top of her shopping list after she bowed out of the Australian Open on Friday with winnings of $57,400 for her third-round finish.

Keys, one of the bright young talents in US tennis, who is hoping to take the mantle from the Williams sisters, struggled with nerves during her center court debut at Melbourne Park and lost 6-2 7-5 to German fifth seed Angelique Kerber.

The 17-year-old vowed to use the match as a learning experience as she prepares for her first full year on the WTA tour.