Fourth-seeded Venus Williams survived a tough second round match with an groin injury at the Austrlian Open here on Wednesday.

The seven-time Grand Slam winner came back from one set down to beat Sandr Zahlavova from Czech Republic by 6-7(6), 6-0, 6-4 in over three hours in Rod Laver Arena.

The former World No. 1 called an injury timeout after the first set and came back with thick bandage around her right leg-end. However, she had never thought of retiring although she could hardly move on the court as normal due to the pain.

"I carry on because I want to know at the end of the day that I gave a hundred percent," said Williams, who hasn't ever retired from a match in over 10 years. "When I look back, I have no regrets that I could have done more or I could have done less, whatever it may have been."

She added that being in a slam really motivated her to stay on the court.

"Being a major I definitely gave it my best," she said. "It wasn't easy out there at all. Had it not been a major, would have definitely been harder to continue."

The 30-year-old veteran will have 48 hours to recover from that possible muscle strain before her next round in Melbourne.