It was a surprise that Wimbledon champion Serena Williams decided to enter the Swedish Open just days after winning her third Grand Slam event of the year.

It's not as much of a surprise that Williams quickly has exited the Swedish Open in Bastad.

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The world's top female tennis player withdrew from the event Thursday, one day after opening the tournament with a victory, wtatennis.com is reporting. Williams cited an elbow injury that flared up during her practice session.

I was having some pain in my right elbow," Williams told reporters at a press conference that was supposed to preview her second-round match against Klara Koukalova. "I felt it a little bit in my match yesterday, and then it got better, but then this morning I really couldn't hit serves, and if I'm not able to hit serves that could definitely be a problem. So I talked to my coach about it and we were like, 'Let's see what the doctor says, and see what everyone else says, and go from there.' The main thing is that we don't want it to get worse; we obviously want it to heal.

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"Unfortunately I haven't had time to heal. I've been going, going, going, playing tournaments I love, and coming here has been such a great joy, but unfortunately it's not going to heal if I keep playing."

The question wasn't so much why she withdrew as why she even entered after during the two-week Wimbledon run.

"This was a really difficult decision, and uncomfortable, because if you know me, you know I really wanted to come here. I love being here and I feel like I'm on vacation here, and it's just a wonderful time. It was a really tough decision, but unfortunately I think I had to make the hard decision.

"I'm in no hurry to leave Bastad. I love this city. Hopefully I'm welcome to stay a few more days!"

The injury, as of now, doesn't appear to be any kind of hindrance to her attempt to complete the calendar Grand Slam next month at the US Open. She is scheduled to play in three events before going to New York. Williams did not compete in any events between the French Open and Wimbledon.

But with her potential to tie Steffi Graf's modern-day record of 22 Grand Slams and become the first since Graf in 1998 to win all for slams in the same year, Serena needs to get better advice from her handlers about managing her schedule.