Martina Hingis and Chan Yung-Jan first paired up in Doha, and a dominant season has seen this dynamic duo ascend to the top two spots in the doubles rankings and be the first of two teams to qualify for the WTA Finals.

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1. Captured nine titles this season - including their first Grand Slam as a duo. The pair have enjoyed a trophy-laden season, capped off by claiming the US Open crown - their first Grand Slam as a duo.

They’ve also won the BNP Paribas Open, Mutua Madrid Open, Internazionali BNL d'Italia, Mallorca Open, Aegon International Eastbourne, Western & Southern Open, the Dongfeng Motor Wuhan Open and China Open.

2. Double and double and double and double the fun. Chan and Hingis have been dominant all season long, and it’s shown in how many times they’ve won back-to-back titles.

They’ve claimed four “doubles” so far this season: in Madrid-Rome, Mallorca-Eastbourne, Cincinnati-US Open and Wuhan-Beijing.

3. They’re undefeated in finals in 2017. The pair’s win-loss record for the year might be remarkable - they’ve only lost six matches together - but their record in finals is even more impressive. They’re undefeated in finals to date, recording a flawless 9-0.

In fact, Chan and Hingis have advanced to at least the quarterfinal stage or better in every single tournament they’ve competed in.

4. Their dominant season has seen them rise to the top of the rankings. After their triumph in Wuhan, Hingis shot to the top of the WTA doubles rankings, returning to World No.1 The Swiss star has previously held the top doubles ranking for 66 non-consecutive weeks, having first climbed to the top of the ladder on June 8, 1998 at 17-years-old to become the youngest-ever doubles No.1.

But partner Chan, who is sitting at a career-high World No.2, is hot on her heels...

5. They’re going back to Singapore - this time together. Chan and Hingis were at opposite sides of the net at last year’s BNP Paribas WTA Finals Singapore presented by SC Global, but now they’ll be teaming up together.

Chan will be making her fourth appearance and Hingis will be making her eighth doubles appearance at the WTA Finals, where she has won the doubles title on three occasions in 1999-2000 (with Anna Kournikova) and 2015 (with Sania Mirza).

“It is a great honor to be the first team to qualify for the BNP Paribas WTA Finals Singapore,” Hingis said. “Yung-Jan and I teamed up for the first time earlier this year and we have had great success.”

“This will be my fourth time competing at the WTA Finals in Singapore, and I’m really looking forward to it,” Chan added. “The last two years have been with my sister, and we have played against Martina many times, so it will be a fun new experience to play in Singapore with her on my side of the net.”