The WTA Tour kicks off its 2018 with tournaments in Brisbane, Auckland and Shenzhen. The biggest storyline heading into the first week of the new year is the race for the number one ranking.
Simona Halep currently holds that distinction, having taken the top spot in October when she reached the final of Beijing. Her reign could end this week as she leads Garbine Muguruza by just 40 points.
The Spaniard was previously at the summit after her fourth round showing at the U.S. Open. Halep took over at #1 after Muguruza retired in that very same tournament in Beijing.
Caroline Wozniacki is the third player with a chance to claim the #1 ranking after week one of the new season. The Dane won the WTA Finals in Singapore and finished at #3, her highest ranking since 2011.
Here is how the battle for the rankings lead will play out in the opening week of the season.
The scenarios for all three players
It's pretty clear for the Romanian: win the title in Shenzhen and she will stay at #1. Halep won the tournament in 2015 and lost to eventual champion Kateřina Siniaková last year.
Should she fail to win in China, Muguruza can reclaim the #1 ranking, but she must reach at least the final in Brisbane, a tournament she has never finished.
In the past three years, she withdrew in 2015 with an ankle injury before the tournament began, in 2016, a left foot injury caused her to retire in the second round and last year, she pulled out five games into her semifinal match.
Muguruza can apply the pressure with a win in Brisbane, forcing Halep to win Shenzhen. A runner-up finish for the two-time major champion means the Romanian needs at least a semifinal showing.
An odd scenario could take place where the top two finish in a tie. If Muguruza finishes as runner-up in Brisbane and Halep is a semifinalist in Shenzhen, they would both have the same ranking points.
Halep holds the tiebreaker and would stay at #1 as she has more points among WTA Finals, Grand Slams, Premier Mandatory and Premier 5 events over the last 12 months with 5,636 as compared to Muguruza's 5,396.
For Wozniacki, a return to #1 for the first time since 2012 offers her only one path. She needs to win in Auckland with Muguruza losing before the final in Brisbane and Halep losing before the quarterfinals in Shenzhen.
Brisbane and Shenzhen kick off on New Year's Eve while Auckland begins on New Year's Day.