TORONTO (CNN) – A week after suffering the worst defeat of her tennis career, Serena Williams has admitted that she is struggling with “postpartum emotions,” and has felt in a “funk.”

On her Instagram page, the 23-time grand slam champion revealed the struggles, which saw her lose 6-1 6-0 to Johanna Konta at the Silicon Valley Classic. She withdraw from this week’s Rogers Cup in Toronto.

“Last week was not easy for me,” said Williams in her Instagram post. “Not only was I accepting some tough personal stuff, but I just was in a funk.”

“Mostly, I felt like I was not a good mom,” Williams added.

Last week was not easy for me. Not only was I accepting some tough personal stuff, but I just was in a funk. Mostly, I felt like I was not a good mom. I read several articles that said postpartum emotions can last up to 3 years if not dealt with. I like communication best. Talking things through with my mom, my sisters, my friends let me know that my feelings are totally normal. It’s totally normal to feel like I’m not doing enough for my baby. We have all been there. I work a lot, I train, and I’m trying to be the best athlete I can be. However, that means although I have been with her every day of her life, I’m not around as much as I would like to be. Most of you moms deal with the same thing. Whether stay-at-home or working, finding that balance with kids is a true art. You are the true heroes. I’m here to say: if you are having a rough day or week–it’s ok–I am, too!!! There’s always tomm!

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“I read several articles that said postpartum emotions can last up to three years if not dealt with. I like communication best. Talking things through with my mom, my sisters, my friends let me know that my feelings are totally normal.” the tennis pro continued. “It’s totally normal to feel like I’m not doing enough for my baby.”

It is thought that as many as one in five women will suffer from some form of depression, mood or anxiety disorder during or after pregnancy.

Williams, who finished runner-up at Wimbledon last month, recently returned to tennis after giving birth to her daughter in September. The birth involved an emergency C-section, a procedure which led to serious health complications which she was “lucky to have survived.”

Serena Williams

(credit: Ezra Shaw/Getty Images)

In her Instagram post, the 36-year-old tennis star went on to offer reassurance to other moms who may be struggling to cope with the challenges of motherhood. “We have all been there,” she said. “I work a lot, I train, and I’m trying to be the best athlete I can be.”

“That means, although I have been with her every day of her life, I’m not around as much as I would like to be. Most of you moms deal with the same thing. Whether stay-at-home or working, finding that balance with kids is a true art,” explained Williams. “You are the true heroes.”

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