Hingis out after op

Injury ended Hingis's hopes of staying at number one

Martina Hingis will miss the remainder of the season after having surgery on damaged ankle ligaments.

The 21-year-old underwent an operation in Zurich after twisting her right ankle in her semifinal against Lindsay Davenport at the Filderstadt Grand Prix on Saturday.

Surgeon Heinz Buehlmann, who performed the operation, said she would be out of action for around two months.

He said: "I think she will be able to start running again in six to eight weeks and be back on the court and training in two months."

Seventeen months as number one

Hingis will be overtaken by Jennifer Capriati at the top of the world rankings on Monday.

She had been in the number one position since May last year but needed to reach the Filderstadt final to remain at the top.

Hingis will miss her home tournament, the Swisscom Challenge, which began on Sunday.

France's Sandrine Testud, the highest-ranked non-seeded player, will take her place in the main draw.

Swisscom Challenge Tournament director Beat Ritschard said: "My concern is not that the tournament is losing its number one player.

"First and foremost, I sympathise with Martina and wish her all the best for a quick recovery."