"I don't know what to do with a baby", she said at the time.
Serena won the Australian Open championship while pregnant, but then announced she'd be taking a hiatus from tennis to focus on becoming a mum.
"I can not have the same success as I had with Serena with everyone", he said. "That's all right now".
Since giving birth on Labor Day weekend, social media users have found a bit of humor in the timing.
"Well, I'm very happy for her. I've been so good about it, but this was the one time it slipped". "Words can't describe", she told ESPN.
Should she beat Suarez Navarro, it would set up a big-time clash with the victor of the Petra Kvitova-Garbine Muguruza fourth-rounder.More news: Japan condemns North Korea after launch of medium range ballistic missile
'So baby's head is here, ' she explained as she pointed to her lower abdomen.
"Oh, my gosh", Venus said.
Williams will face Carla Suarez Navarro in her next match. "And if she doesn't put her career first, I think she will stop", he added.
'We have a lot of work ahead of us'. "We actually use the English language".
"Obviously I'm super excited", said the baby's aunt, Venus Williams, as she took the court at the US Open.
The US Open Tennis official Twitter account tweeted a video message of congratulations to the sporting star on Friday, which included heartfelt tributes from tennis pros from around the world.