The Australian Open tennis campaign of Japanese star Kei Nishikori may well be over before it has begun.
The world number 18 has succumbed to a knee injury and pulled out of the Kooyong Classic lead-up event, due to begin on Wednesday.
Nishikori, an Australian Open quarter-finalist last year and winner of the Japan Open, withdrew from last week's Brisbane International and said on Tuesday he had not yet tested his knee.
However, after hitting at Melbourne Park, he felt he was not fit enough to compete at Kooyong and will use the remainder of the week undergoing intensive treatment to try to play in the Open.
Nishikori has been replaced in the field at Kooyong by Croatian Ivan Dodig, a 28-year-old ranked 74 in the world.
Despite the issue, the Japanese was upbeat about his chances of taking his place in the Open field.
"It's not bad - let's cross the fingers and hopefully it will be okay," he said.
Nishikori is the second player to withdraw from the exhibition event before its start.
Earlier, world number 12 Juan Monaco of Argentina pulled out on the eve of the tournament due to a hand problem.
Tournament director Colin Stubs said Monaco's management told him they were uncertain how serious the problem was but doctors had advised him not to play in the next few days.
Monaco's spot in the eight-man field was taken by world number 58 Paul-Henri Mathieu of France.
AAPTags: sport, tennis, melbourne-3000, japan First posted January 09, 2013 11:09:13