Early indications suggested the world number 11 could well make a recovery and return to the sport, where she has been a mainstay in the top rankings for the past five years.

"The scale of the injury is serious, but Petra is young and strong, according to the surgeon, who sees no reason why she could not return to playing tennis," Karel Tejkal, spokesman for the Czech Fed Cup team, said.

Doctors operated on all five fingers of her left hand and she will not be able to exert pressure on the injured hand for three months to let repairs to tendons heal, he said.

Boiler inspector

Kvitova had said on social media before undergoing surgery that the attack by an individual with a knife on Tuesday had left her "shaken, but fortunate to be alive".

The assault took place in her flat in the city of Prostejov, about 260 km (160 miles) southeast of Prague, the location of a tennis club where she, men's world number 10 Tomas Berdych and other top-ranked Czech players often train.

Czech media reported the intruder presented himself to Kvitova as a boiler inspector.

The seriousness of the injuries raises questions about how they will affect her career as a tennis player.

Kvitova, 26, has won a total of 19 tournaments, including the 2011 and 2014 Wimbledon titles.

Tuesday's incident occurred shortly after Kvitova had withdrawn from next week's Hopman Cup in Perth as she continues to recover from a stress fracture in her foot.

She is to be replaced at the Australian even by fellow Czech Lucie Hradecka.

In 1993, then-world number one Monica Seles was stabbed courtside during a break at a tournament in Germany by a man who admitted having an obsession with her rival Steffi Graf. The attack forced Seles out of tennis for two years.

pfd/jh/idr (AP, dpa, Reuters)