Meet the eight WTA Finals title contenders

The battleground is set in Singapore as eight women have risen through the pack and will duke it out in the season-ending tournament, the WTA Finals. Each player has had different seasons—this week will be as unpredictable as their playing styles. Two days of matches have already been completed, but with a lot of tennis left to be contested, here are all the player breakdowns.

1

Rank: No. 1

Best Appearance in Singapore: 2014 final

Best Moment in 2017: The Romanian became the first tennis player from her country become world No. 1, accomplishing the feat after defeating Jelena Ostapenko in the semifinal of the China Open. Halep could have taken the top ranking at the French Open, but was defeated by the youngster in the final.

Worst Moment in 2017: While Halep's season eventually became one of the best in her career, the year didn't start off that way as she lost to a then-ranked No. 52 Shelby Rogers in the first round of the Australian Open.

2

Rank: No. 2

Best Appearance in Singapore: 2015 semifinals

Best Moment in 2017: After winning the French Open in 2015, but then not having a great followup season in 2016, the Spaniard came back with a vengeance this year. She won Wimbledon, becoming a multiple Grand Slam champion and silencing any critics that doubted her.

Worst Moment in 2017: It's hard to pick a bad moment for Muguruza because she has had such a stellar year. However, she hasn't been flawless, and one of her biggest hiccups was losing in the first round of Madrid against Timea Bacsinsky. It especially hurts because it happened in her home country.

3

Rank: No. 3

Best Appearance in Singapore: 2016 first round

Best Moment in 2017: Pliskova found solid footing in the middle of the season, reaching the semifinals of the French Open and then following it up with a title win in Eastbourne over Caroline Wozniacki. That was her third title of the year and continued her strong push towards the WTA Finals.

Worst Moment in 2017: Unlike Eastbourne however, the Czech couldn't quite make as big of a name for herself in Dubai where, after defeating Wozniacki in Doha where she won the title, she lost in the first round.

4

Rank: No. 4

Best Appearance in Singapore: Debut

Best Moment in 2017: Svitolina has won four titles in 2017, but her most important trophy capture was in Toronto, where she defeated four of the year's WTA Finals competitors in a row: Venus Williams, Muguruza, Halep, and then Wozniacki in the final.

Worst Moment in 2017: Losing in a Grand Slam is never easy. The Ukranian lost in the third round of the Australian Open, and while that may not seem terrible, Svitolina has never made it past that point in Australia during her career.

5

Rank: No. 5

Best Appearance in Singapore: 2008 champion

Best Moment in 2017: Reaching the Australian Open final is no small feat, but it was made even more impressive by Williams' ability to hang on to her top level of play at 37 years old. Her final against sister Serena gave fans possibly one last look at an era that refuses to let go.

Worst Moment in 2017: It may seem strange to put the Wimbledon final as Venus' worst moment, when her Australian Open final was her best. Australia was a showcase of her ability to stay in top level play, while her lost match against Muguruza in London was a display of how far she really is from the top spot.

6

Rank: No. 6

Best Appearance in Singapore: 2010 finalist

Best Moment in 2017: This year has been a resurgent one for Wozniacki, who has made somewhat of a comeback since falling outside of the Top 50 in 2016. It took six final appearances in various tournaments, before finally snagging her first title of the year in Tokyo at the Pan Pacific Open.

Worst Moment in 2017: While any of her final losses could be her Worst Moment, due to the emotional toll it takes to constantly miss out, her loss in the final of Toronto stands out. It was her second loss to Svitolina in a 2017 final. Maybe the Dane will get some revenge in Singapore.

7

Rank: No. 7

Best Appearance in Singapore: Debut

Best Moment in 2017: Obviously Ostapenko's triumph in the French Open stands out as not just the best moment of 2017, but the greatest moment of her career so far. Defeating Halep in three sets makes this year's WTA Finals far more interesting and hard to predict.

Worst Moment in 2017: Miami wasn't the best showing by Ostapenko. She fell to Madison Brengle, a qualifier who was ranked No. 86 in the world. While she quickly recovered and went on to have a great season, the loss stands out because it was at one of the top tournaments on tour.

8

Rank: No. 9

Best Appearance in Singapore: Debut

Best Moment in 2017: Garcia's most recent title winning streak, Wuhan and then Beijing, is of considerable note, not just because she won back-to-back tournaments, but because of the caliber of opponents she had to defeat. She took out Angelique Kerber, Halep and  Svitolina, to name a few.

Worst Moment in 2017: Losing in the first round of a Premier Mandatory tournament is always disappointing. Unfortunately, Garcia found herself in that situation in Rome, as she couldn't keep up with qualifier Qiang Wang.