SHENZHEN, China - No.2 seeds Barbora Strycova and Hsieh Su-Wei kicked off their doubles campaign at the Shiseido WTA Finals Shenzhen with a hard-fought win over Australian Open champions Samantha Stosur and Zhang Shuai. 

Strycova - who is in the hunt to finish the season with the WTA Year-End Doubles World No.1 Ranking - and Hsieh were one of the most dominant doubles duos in 2019, lifting the trophy at Wimbledon, Madrid, Dubai and Birmingham. 

Read more: Doubles field set at 2019 Shiseido WTA Finals Shenzhen

They carried all of their momentum into the WTA Finals, where they’re making their debut as a team. The pair rallied back after dropping the second set to take the match in a tiebreak, 6-4, 4-6, 10-5. 

“It’s always good to start with a win, and it was a very tight match with both sets quite equal,” Hsieh told press after the match. “But thankfully we are the winners, and I thought our performance was very solid today. We are both extremely happy.”

Also in action, No.6 seeds Barbora Krejcikova and Katerina Siniakova had a more straightforward path to victory against No.4 Gabriela Dabrowski and Xu Yifan, winning 6-4, 6-2 in the second doubles match of the night. 

“I think we played really good, aggressive, and my partner helped me a bunch of times,” Siniakova said in a post-match interview. “I think we’re pleased with this one.”

“It was really difficult playing this late, it’s never easy,” added Krejcikova. With all three previous singles and doubles matches on Center Court going the distance, the pair took the court at nearly midnight. “It was also difficult because we played them already this year, and we never won a match. So this one, I’m really happy and proud that we were able to finally beat them.”

Barbora Krejcikova and Katerina Siniakova in action at the Shiseido WTA Finals Shenzhen. (Getty Images)

Krejcikova and Siniakova’s straight sets win puts them at the top of the Purple Group, and the pair could advance to the semifinal knockout stage with another two-set victory on Tuesday. Conversely, Dabrowski and Xu would be eliminated if they suffer another straight sets loss. 

But if Krejcikova-Siniakova and Dabrowski-Xu win on Tuesday, Krejcikova-Siniakova would qualify as group winners while Stosur-Zhang are eliminated. If Hsieh-Strycova and Stosur-Zhang win their next matches, then it’s Hsieh-Strycova that would qualify as group winners while Dabrowski-Xu are eliminated. 

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Any other combination of results will mean qualification for the semifinal will come down to the final Purple Group matches on Thursday.

“The [round robin format] is different, and it means every match is important,” Siniakova said. “I’m glad that they changed it [from only knockout rounds]. But we’re just going to fight for every match and we would like to show our best tennis. Hopefully we can win as many matches as we can.”