"It's very disappointing for the tournament because she is a great player," Dementieva said after defeating 18-year-old compatriot Anastasia Pavlyuchenkova 6-4 6-4.
"We have had some great matches. I always like to play against her. It is a great experience. But you saw her in Australia with all that taping on her leg and she still produced a great win.
Story continues below ↓advertisement | your ad here"So it is not surprising that she isn't here -- especially as she is always playing to win a tournament and pushing herself."
Williams defeated Justine Henin in the first grand slam of the year despite heavy strapping on her right thigh and left knee.
"I wasn't at 100 per cent today. I was a bit up and down but it is good to get a win," Dementieva added.
The 28-year-old, who reached the final last year, is the top seed in Paris following Williams's withdrawal.
Dimentieva will face the winner of Thursday's second round match between German Andrea Petkovic and France's Aravane Rezai,
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