'I just want to put that out there. That's, like, three months after I give birth. I'm not walking anything back, but I'm just saying it's pretty intense.'
Serena Williams aims to defend her Australian Open title next year, the American saying the rapid return to action would only give her around three months to prepare after giving birth to her first child.
The 23-times Grand Slam winner announced her pregnancy in April and will be on maternity leave for the rest of the year.
The 35-year-old is engaged to Reddit co-founder Alexis Ohanian.
"It's the most outrageous plan," Williams told Vogue magazine. "I just want to put that out there. That's, like, three months after I give birth. I'm not walking anything back, but I'm just saying it's pretty intense.
"If I lose and I lose again, it's like, 'she's done'. Especially since I'm not 20 years old. I'll tell you this much: I won't win less. Either I win, or I don't play."
The American added that she could have a few new tricks up her sleeve after analysing her game on television over the last few months.
"I learn by watching. Or I watch old matches of myself on the Tennis Channel," she added.
"I hit amazing shots and these girls are running them down and hitting winners, and I'm beginning to see why. It's because I have patterns."
Williams is one Grand Slam shy of Australian Margaret Court's long-standing record of 24 major titles.
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Serena had no intention of sharing her pregnancy news