Hingis steps up fitness bid for U.S. Open

Former world number one Martina Hingis has stepped up her bid to compete in next month's U.S. Open with an intense training programme in Florida, Switzerland's Blick newspaper reported on Thursday.

Swiss Hingis, the 1997 U.S. Open champion, is struggling to shake off the ankle injury which kept her out the French Open and Wimbledon in time to compete in the Flushing Meadows tournament, which begins on August 26.

The ankle was operated on in May but is still swollen and her representatives failed to submit an application to enter the U.S. Open by the July 15 deadline.

On Monday Hingis claimed she could still compete thanks to an invitation if she is declared fit before the start of the final grand slam of the year.

Blick were given an insight into her training camp in Saddlebrook, Florida, which involves an intense programme including at least three hours of tennis a day as well as cycling, swimming and skating.

"I must watch out not to overload the foot sometimes," Hingis told Blick.

Hingis has won five Grand Slam titles. She reached the final of the Australian Open earlier this year but lost to defending champion Jennifer Capriati.