The suit - which Williams said made her feel like a "superhero" - was created to help the new mum's circulation and help prevent blood clots.
On the other hand, Naomi Osaka has become the first ever tennis player from Japan to hold a grand slam title as she beat Williams 6-2, 6-4 in the summit face-off at the Arthur Ashe Stadium in NY.
Naomi ended up winning her first Grand Slam title following the controversial decision.
Williams lost her calm and out loud abused the umpire, calling him a "liar" and a "thief".
"Every day I step out on this court I am so grateful I have an opportunity to play this sport".
"Congratulations Naomi", said Williams, who later said Osaka played an "amazing" match. 'I knew playing against her, I felt like, you know, I needed to get to the net a little bit more.More news: Petrol, Diesel Prices At Fresh Record Highs; Andhra Announces Cuts
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It was left for others to go beyond Williams' remarks to reporters and King, a pioneer in women's rights and sports, quickly stepped up.
She was up 2-1 on the changeover when she spoke again with Ramos appearing to smooth things over, and she finally found a way to break Osaka for a 3-1 lead.
That's actually the most exciting part.' Serena played one of her best match in the semifinals against Anastasija Sevastova beating her 6-3 6-0.
"I didn't get coaching". Her ugly rant at a line judge marred Kim Clijsters's semi-final win over her in 2009 and she infamously called chair umpire Eva Asderaki "unattractive inside" in a tantrum during her 2011 final loss to Samantha Stosur.
"How dare you insinuate that I was cheating?"
"A year ago I was fighting for literally my life at the hospital after I had the baby", said Williams, who is ranked No. 26 in the world.
"It's hard to say because I always fight till the end and I always try to come back, no matter what".