Kei Nishikori announced Saturday that he will skip the upcoming Rakuten Japan Open and Shanghai Masters due to pain in his right arm and elbow.

"I have some good news and some bad news. These past days I sat down with my medical team to continue monitoring my arm/elbow. This has been bothering me since the French Open (May 26-June 9) off and on," Nishikori said on his official app.

"The good news is that there is great progress, it's healing, and I am finally close to being pain free. Structurally my arm and elbow look good."

"The bad news is that we are not 100 percent there yet. There is still swelling and fluid in the arm/elbow and the doctors feel it's in my best interest to take 3-4 more weeks off without tennis."

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The Japanese world No. 8 has not played in a tournament since losing to Australia's Alex de Minaur in the third round of the U.S. Open, the fourth and final Grand Slam of the year.

"I am so sad to say that I will not be able to play the Japan Open, Shanghai Masters," Nishikori said. "The Asian swing is obviously one of my favorite times of the year and I will work hard to come back stronger."

Nishikori, who has won the Rakuten Open twice and finished runner-up last year, will also miss a scheduled charity match with Swiss No. 3 Roger Federer on Oct. 14 in Tokyo.