NEW YORK—Naomi Osaka limped out of Cincinnati last week with a left knee injury.

The world No. 1 practiced at the US Open wearing a knee brace today while speculation continues to swirl around her health.

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The defending US Open women's champion joined men's champion Novak Djokovic and ESPN's Chris McKendry, Mary Joe Fernandez and Jason Goodall on stage for the US Open draw ceremony outside Arthur Ashe stadium.

Asked to address the state of her knee, Osaka was purposefully vague.

"If you watched me play that's the update—it's getting better," Osaka said. "I'm a fast healer so I'm kind of banking on that.

"I mean I'm here. I feel as healthy as I can be."

The top-seeded Osaka opens against Anna Blinkova. Fifteen-year-old American phenom Coco Gauff resides in Osaka's section of the draw; the pair could potentially face off in the third round.

Two-time Grand Slam champion Osaka has been making sponsor appearances as well, including a Nike event in SoHo on Tuesday.

Photo credit: @CincyTennis