INDIAN WELLS, CA, USA - No.8 seeds Latisha Chan and Chan Hao-Ching have burst into their first Premier Mandatory semifinal of the year at the BNP Paribas Open, continuing a streak of doubles success since the sisters reunited at the beginning of the season.

The pair needed a super-tiebreaker to see off the No.3 seeded team of Hsieh Su-Wei and Barbora Strycova, 4-6, 6-2, 11-9 to book their semifinal spot on Tuesday. The result backs up a strong start to 2019, which has seen the sisters from Chinese Taipei lift two trophies - Hobart and Dubai - and record a run to the Australian Open quarterfinals and Brisbane final.

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Latisha, 29, and Hao-Ching, 25, are the second-most successful WTA sister duo on the doubles court after, of course, Serena Williams and Venus Williams. But despite racking up 12 titles together, the Chan sisters have recently competed separately more than they have done together after breaking up in 2017.

“I mean… to be honest, playing with your sibling is not that easy at the beginning,” Latisha explained. “Also, we started when we were pretty young, and when you’re not that mature, it’s tough.

“And we are four years apart in age so some types of level, tennis or mental, especially when you are that young your levels can be so different.”

Although they had captured eight titles together, the pair parted ways in 2017 to seek success with other partners after reaching their breaking point: a string of poor results that had begun to grate on the sisters’ relationship.

“I would start to be angry, or like, I could understand what happened after a match but we’d have some misunderstandings with each other,” Latisha explained.

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After their sister act split, Latisha paired with Martina Hingis and the pair claimed a whopping nine titles together - including Chan’s first Grand Slam at the US Open - and rose to co-WTA World No.1s. Hao-Ching, who also goes by ‘Angel’, on the other hand bounced between different partners as she steadily built up the wins to chip away at her doubles ranking and claim one title (Dubai 2018 with Zhaoxuan Yang).

Two years of spending time together just as sisters - without the pressure of a doubles partnership on top of that - was crucial for the Chans, who decided during the off season to give things another go.

“We are the one who is closest in our lives - so you can be really straightforward,” Latisha explained. “That can be a bonus, but it can also be a thing that’s against us. So I’m happy that finally now we are mature enough to manage that.”

Previously, the pair had discussed reuniting in 2020 to represent Chinese Taipei at the Olympics in Tokyo - but Hingis’ retirement and a brief test of their renewed partnership last year confirmed to the pair that they were ready to take the court again together as equals.

Latisha laughs, “I mean now she can beat me! In the rallies when we’re practicing, I’m like, “How can you beat me?”

“She still don’t believe that!” Angel cuts in.  

“Now I start to accept it as normal,” Latisha adds. “I mean, she’s at her best age, and I’m getting old!”

Up next, they’ll face a big test of their sibling bond when they take on the No.1 seeds and two-time reigning Grand Slam champions Barbora Krejcikova and Katerina Siniakova in the Indian Wells semifinals. The Czech duo edged past Donna Vekic and Kiki Bertens 6-1, 7-6(2) earlier in the day to book the blockbuster clash.

“The Czech girls are the best team in the world,” Latisha acknowledged. “We have played them last year in Miami and that was one year ago, so it will be interesting to watch that match. With Kiki and Vekic, they can be playing some surprising shots or surprising strategies.

“So I think we need to do some scouting and do some homework, and stay focused.”

Read more: Top seeds Krejcikova, Siniakova survive Indian Wells doubles battle 

No.5 seeds Gabriela Dabrowski and Xu Yifan will contest the bottom-half semifinal against the unseeded duo of Elise Mertens and Aryna Sabalenka.

Top 5 most successful all-sister doubles duos:
22 - Serena Williams & Venus Williams
12 - Chan Hao-Ching & Chan Yung-Jan
3 - Lyudmyla Kichenok & Nadiia Kichenok
3 - Alona Bondarenko & Kateryna Bondarenko
3 - Karolina Pliskova & Kristyna Pliskova