Former world No. 1 Maria Sharapova has admitted she is not fully prepared for the US Open.
Sharapova, 30, is competing at her first Grand Slam since January 2016 following a lengthy and complicated drug ban.
The Russian made her WTA Tour return in April 2017 following an initial two-year ban from the International Tennis Federation (ITF) -- eventually reduced to 15 months -- for testing positive for meldonium.
"I haven't had the best preparation [for the US Open] if I am honest," Sharapova said on the tournament's official Periscope channel.
"The tournaments I was supposed to play, I had to withdraw with injury which was quite disappointing."
Sharapova, who has already completed the career Grand Slam, has not competed at the Australian Open, Roland Garros or Wimbledon this year -- the second of which she was refused a wildcard entry.
"After healing for many weeks and skipping Wimbledon and now to skip the warm-up tournaments is disappointing.
"I was so ready, I love playing in the United States and Canada. I have spent a lot of time in Florida training and I was just so happy to get on the plane to New York."
Sharapova holds an impressive record at the US Open -- in 10 appearances she has reached two semifinals and claimed the singles crown in 2006.
Her last match at Flushing Meadows came in 2014 when she lost in the fourth round to Caroline Wozniacki 4-6, 6-2, 2-6. This year's edition begins Monday.