One of the main questions at the start of any round-robin competition like the upcoming WTA Championships is which group is tougher. There's no easy answer to that this year, partly because both No. 1-ranked Simona Halep and 23-time Grand Slam winner Serena Williams are absent from Singapore.
The Red Group has an edge in Grand Slam titles won in 2018 (2-1), thanks to Naomi Osaka and Sloane Stephens. But the White Group boasts a significant lead in total titles collected this season (13-8) and features the defending champion and highest-ranked player in the field, No. 2 Caroline Wozniacki.
But this is not a Grand Slam, and the format is different than any other event on tour. Who has the edge? We looked at the players' current form, degree of difficulty within their group, history in Singapore and anything else we could think of to give you our ... WTA Finals Power Rankings and predictions:
1. Naomi Osaka, red group
2018 W-L: 43-18, 2 titles
When Osaka won the US Open, we wondered what she would do in the ensuing months largely because of Stephens' enormous letdown after she won her first Grand Slam at the same tournament a year earlier. But Osaka backed up her breakthrough in New York with a run to the final in Tokyo and had a semifinal showing in Beijing in the two tournaments she's played since. She will enjoy the indoor hard courts. Osaka might also be eager to log a controversy-free win in a high-profile event. She has a lot of momentum going in and has earned recognition as the top contender.
2. Caroline Wozniacki, white group
2018 W-L: 40-15, 3 titles
Didn't it seem like Wozniacki all but disappeared this season after she won her long-deferred maiden major at the Australian Open? In reality, she's remained right in the mix at the top, always within striking distance. That will make her dangerous at this event. Wozniacki loves these courts, and she's coming in with her confidence replenished after a title in Beijing earlier this month. Only fellow qualifier Petra Kvitova has had fewer losses this year. Want more? Wozniacki is 6-1 against top-10 opponents over the past year.
3. Kiki Bertens, red group
2018 W-L: 48-10, 3 titles
Why so high on this list, when Bertens should count herself lucky just to qualify with such low a ranking? Well, this tournament often spins out a big surprise, and Bertens is a proven disrupter of the status quo. As the beggar at this banquet, she'll be motivated to take full advantage of this great opportunity. Something happens to top-10 opponents when they meet Bertens. She was 10-5 against them this year and even better, 7-3, against fellow Singapore qualifiers, including wins in her past six such encounters. Bertens' biggest title this year came in Cincinnati, where she knocked off No. 1 Halep after wins against, among others, Elina Svitolina and Wozniacki.
4. Karolina Pliskova, white group
2018 W-L: 47-21, 2 titles
If you didn't know better, you would almost think the 26-year-old Czech is employing some sort of gamesmanship. Historically, she has faded right when a breakthrough is within reach, and Pliskova has taken some very tough losses to good players this year. But since her setback against Williams in the US Open quarterfinals, Pliskova has reached two finals, beating Osaka in Tokyo and bowing to Caroline Garcia in Tianjin. The indoor hard courts of Singapore will be ideal for Pliskova's serve and power-forehand game. The question remains: Does she have to grit to close the deal at a big event?
5. Sloane Stephens, red group
2018 W-L: 33-18, 1 title
Stephens relies on inspiration more than any other player in the field, so picking for or against her is always akin to gambling. But she's been to see the elephant, so she'll know what to do if she's in a position to win. The round-robin format allows a player to advance even if she's lost a match (or even, in some cases, two), which really helps a player who is prone to ups and downs like Stephens. The surface is suited to her game. Her record against fellow qualifiers is solid. Stephens has beaten Kerber and Svitolina this year and lost only to Pliskova. If Stephens can navigate her unpredictable group ... watch out.
6. Angelique Kerber, red group
2018 W-L: 45-17, 2 titles
Since taking Wimbledon in July, Kerber has won just five completed matches. And in a surprising move just days ago, she fired her coach, Wim Fissette. While Kerber's title at the All England Club in July has provided the icing on the cake of her comeback, it might have ruined her appetite. She played a load of matches against top-10 opponents, but Kerber went just 5-8 with only two wins over individuals in this field, Kvitova and Pliskova. Both of them are in the opposite group.
7. Petra Kvitova, white group
2018 W-L: 47-14, 5 titles
Kvitova had a scorching start to the year, earning five titles by mid-June, when she served her way to the trophy on Eastbourne grass. Then she mysteriously cooled off. Upset in the first round of Wimbledon by No. 50 Aliaksandra Sasnovich, Kvitova compiled a mediocre 9-6 record from there on. She was 7-1 against top-10 opponents this year, but only two of them remained in that elite group long enough to qualify for Singapore. Kvitova's last win against a fellow qualifier was a semifinal triumph over Pliskova in May. Kvitova is also coming off back-to-back first-round losses in her only two tournaments following the US Open.
8. Elina Svitolina, white group
Ranking: No. 6
2018 W-L: 39-15, 2 titles
Svitolina had a great year in 2017, reaching as high as No. 4 in the rankings. She qualified for the WTA Championships but won just one match and failed to survive group play. She's always struggled to come up with her A-game on big occasions. The flexibility of the round robin will certainly help Svitolina relax should the jitters strike, but she could have bigger problems. She hasn't added much to a bread-and-butter game that seemed maxed out a year ago and has, if anything, been less effective this year. Svitolina has just two wins against fellow qualifiers this year and none since February.
Semifinals: Osaka over Pliskova; Bertens over Wozniacki
Final: Osaka over Bertens