Romanian holds the top ranking heading into the first grand slam of the season, but whether she can maintain her status will depend on a number of factors.
Simona Halep - the next undisputed No 1 of women's tennis or another Angelique Kerber?
Twelve months ago it was Angelique Kerber who began the tennis season at the top of the WTA rankings and went to the Australian Open as the No 1 seed.
After an impressive 2017 in which she won two majors and wrested the top slot away from Serena Williams for the first time since February 2013, it looked as if the women's game finally had a new player to consistently lead the sport.
Unfortunately for Kerber, it did not end up that way. She failed to win a title all year, finished with a record of 29-24 and has dropped down to 21st in the rankings.
The pressure of being No 1 now sits with Simona Halep, who will be guaranteed top seed in Melbourne after she beat Duan Yingying 3-6, 6-1, 6-2 in the second round at the Shenzhen Open in China on Wednesday.
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If supporters of the Romanian were looking for positive early signs that she is going to kick on and have a strong 2018, then they would have been disappointed by large parts of the encounter with the world No 91.
It was her Chinese opponent who won the opening set 6-3 with a lone break to put Halep on the back foot.
Halep did fight back to charge through the next two sets for the loss of just three games and set up a last-eight encounter with Aryna Sabalenka on Thursday.
On one hand, it was impressive how she bounced back from the early setback, but dropping a set to a lowly ranked player, no matter how early in the season, is not a great statement of intent to send to the rest of her rivals.
"I knew that she is playing really hard and hitting every ball. I knew I had to be strong on my legs," Halep, 26, said after the match.
"After the first set I was thinking I have to find rhythm, to stay closer to the baseline and open the court better, which I did.
"It was not easy, even though the scores were 6-1, 6-2. It was a very tough match."
Halep is yet to win a major and has that hanging over her shoulders in trying to establish herself as No 1.
Only two of the top six in the rankings, and three of the current top 10, are grand slam champions, which highlights the dominance of 23-time major winner Williams and signals the start of a changing era in women's tennis.
Williams showed some flashes of her best in her exhibition defeat to Jelena Ostapenko at the Mubadala World Tennis Championship in Abu Dhabi.
She also looked like a woman who had not played tennis in a very long time, which of course she has not since the Australian Open last year to be exact, taking time off to give birth to her first baby in September.
Williams is yet to announce if she will play in Melbourne, but with the new challenges of life as a mother to juggle alongside being a tennis player, it is hard to believe she will entertain any kind of schedule that would put her in a position to return to No 1 again.
Halep is in pole position at present to be the player that can enjoy a long run at the top.
She was knocked out in the first round in Melbourne 12 months ago by Shelby Rogers so has no points to defend in Australia.
She can be competitive, as runs to the quarter-finals in 2014 and 2015 showed, and as No 1 she should expect to be able to match that, if not better it.
This could be an unpredictable start to the year in the women's game. How much Williams plays will be of interest, but just who is the player to establish themselves as the new force in the game is yet to be established.
Halep has shown she has the game to be that player. But having deservedly got herself to the top she now needs to seize the opportunity, starting by winning the Shenzhen title and then having a good run in Melbourne.
Whether she can do this, or become another Kerber, is going to be one of the early fascinating narratives of 2018.