Serena Williams' sore shoulder diminished as she prepared for the 2016 U.S. Open and possible tennis history.
Williams equaled Steffi Graf's 22 major singles titles at Wimbledon in July, but her injury was evident in her third-round loss at the 2016 Rio Olympics.
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Competition at Flushing Meadows begins Monday. Williams is the top women's seed and will try to atone for last year's lost in the semifinals.
Despite skipping a recent prep tournament, Williams, 34, admits she is not in great shape despite improvement in the joint.
Asked when her shoulder problems began, Williams replied: "Ironically enough, the day after the finals of Wimbledon. I was like, how did I win?"
"For the Olympics, I just practiced two days before playing my match. It's not ideal, but it was all I could do," she said. "I have not played a lot and practiced a lot. The shoulder is getting a little bit better. I am taking it a day at a time."
Williams said she wanted to prepare more for the Open, "but there is nothing you can do about it and I am going to try to make the best of every single opportunity that I have to play."
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Williams will begin her U.S. Open bid with a match against Ekaterina Makarova, whom she beat en route to the title in 2012 and 2014.
"I know she's a good player. I've just got to do the best I can. She's a big fighter. She never really stops," Williams said. "I think one thing I think that's pretty impressive is she gets a lot of balls back. You think she's not super quick, but she is."