Williams reached the finals at Wimbledon and in NY on what was her comeback year on the WTA Tour in 2018 following the birth of her first child.
Wozniacki, ranked three, started last season by winning her first Grand Slam in Melbourne and returning to world number one, but ended it in October with the bombshell announcement that she had been diagnosed with rheumatoid arthritis.
Combined with the pressure of becoming the first Japanese player to win a major, and the fanatical support that brings, there were fears she could wilt under the spotlight.
That loss left Williams, who also lost in the Wimbledon final previous year, short of matching Margaret Court's marker of 24 grand slam titles, a record the American has another chance of equalling in Melbourne over the next fortnight.
"The fact that she dominated for so long and could break the record of grand slams, I think that will overshadow everything at the end of the day", former world No.1 Evert told a conference call.
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Williams, 37, captured her seventh Australian Open title in her last appearance in Melbourne in 2017, when she was in the early stages of her pregnancy with daughter Alexis Olympia.
Defending champion and third-seeded Caroline Wozniacki, who claimed her first major title past year by beating Halep in the final of the Australian Open, will start the defense of her title against Alison Van Uytvanck of Belgium.
She warmed up for Melbourne by making the semi-finals of the Brisbane International last week, where she blamed a poor attitude for losing to Lesia Tsurenko.
"I have no reason to believe that Sabalenka will not win more than one Grand Slam. Why?" I feel at home here.
Osaka, who turned pro at just 14-years-old, is the fourth seed at the 2019 Australian Open - which begins January 14 in Melbourne. Her experiences have been a learning experience for me.
An indication of the steel that lies beneath her humble demeanour came in her outing after the US Open, the Pan-Pacific Open in Tokyo, when she breezed into the final without conceding a set. "She's the one that we need to watch I think for this year".