Jelena Jankovic has exited 6-1, 6-2 to 17-year-old Zarina Diyas in her opening match at Moscow.
Jankovic would not speak with press after the match but issued comments through the WTA:
"I've been sick since I came from China. I got an infection and have been on antibiotics for a week. I wasn't ready to play at my level. I was suffering but didn't want to retire. I finished as well as I could but it was tough to focus on my tennis. I had a hard time breathing and I was getting tired quickly.
"I will see the doctor now. It's the end of the year and my body is exhausted. It has been a long season with lots of traveling. It's one more tournament to go and I hope I can at least be healthy so I can go out there and play the game. I really need to have energy and be able to smile on court and enjoy the game.
"Doha is a different type of tournament because you can lose a match and still win the whole tournament. So anything can happen, but for me the biggest concern is being healthy. We'll see what happens and hopefully I'll be ready."
Elena Dementieva, playing Luxembourg this week instead of her hometown event in Moscow, pulled out of her second-round match with a foot injury.