Nikolay Davydenko has pulled out of the Australian Open due to a heel injury.
The 27-year-old Russian was participating in the Chennai Open, where he was due to play Czech Lukas Dlouhy in the second round.
"I am pulling out both the Chennai Open and the Australian Open because my left heel has been very painful over the last few days," Davydenko said.
"I will see specialists before I can say when I will return to the circuit."
The world number five revealed that the injury has been bothering him for a number of months.
"The pain in the left heel started last year. It also bothered me during the Masters Cup in Shanghai in November where I reached the final," he added.
"Last week when I was in Abu Dhabi, the pain became worse. Now I cannot run, so there is no way I can play tennis.
"There is no pain when I am not playing. But if I play for a few days, it increases. I don't know what is happening.
"I need to get my heel checked. So there was no way I can play at the Australian Open.
"I usually do not miss big tournaments, but the pain left me with no option to miss Chennai and Australia."
Davydenko defeated Austrian Daniel Koellerer 6-2 6-3 in the first round of the Indian tournament. He has reached the quarter-finals of the Australian Open three times.

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