World No. 3 Coco Gauff and No. 2 Iga Swiatek of Poland won their respective opening matches of the Orange Group at the WTA Finals Riyadh in Saudi Arabia.
Gauff posted a 6-3, 6-2 victory over No. 6 Jessica Pegula, while Swiatek rallied from a first-set misstep to notch a 4-6, 7-5, 6-2 victory over Wimbledon champion Barbora Krejcikova of the Czech Republic.
Gauff and Swiatek will square off on Tuesday, with the winner taking control of the Orange Group. Swiatek holds a commanding 11-1 head-to-head record against Gauff.
Gauff held a 16-8 edge in winners and converted five of her eight break points to end the match in 75 minutes.
"I thought we both were playing high level," Gauff said. "I just think I was able to break through on the more important points."
Swiatek, in turn, struggled in her first match in two months, falling in the first set and trailing 3-0 in the second before she flipped the switch.
"Even though I played a lot of those (practice) matches," Swiatek said. "I kind of forgot for a while how it is to feel all those things, a bit different stress and emotions. For sure, I needed some time to adapt. The most important thing was that even though it happened, I managed to fight through that. And was patient enough to wait to get better."
Swiatek broke Krejcikova early in the third set and seized a 5-0 lead en route to winning the match.
"Honestly, I just focused on getting the balls in," Swiatek said of the early going. "I needed to focus on the easy stuff. My main goal was just to be solid.
"I'm happy that I won because at the beginning I felt a little bit rusty. "
Krejcikova lamented letting the match get away from here.
"It definitely wasn't the best tennis I can play, but I was really quite solid," Krejcikova said. "I just feel I lost a little bit the momentum of the match and obviously, I'm not really sure if it was me or Iga. She just came up and started to play more aggressive, started to hit her targets better.
"Yeah, unfortunately, it's Iga -- and you have to play two sets better than her."
Jiangxi Open
The long wait is over for Viktorija Golubic.
The Swiss player came from a break down in the second set to earn her first win in eight years and second overall WTA Tour championship by defeating No.2 seed Rebecca Sramkova 6-3, 7-5 in Jiujiang, China.
Golubic, 32, won in Lausanne in 2016. Five years later, she reached two finals and the quarterfinal of Wimbledon to climb to No. 35 in the world, but plummeted to No. 168. With this win, she will near the top 100 again.
Sramkova, from Slovakia, went up 2-1 in the second set, then outlasted Golubic in a marathon game that featured 17 score changes to go up 3-1, But Golubic broke her opponent to get back on serve, then broke Sramkova in the final game to win.
Hong Kong Tennis Open
Top seed Diana Shnaider needed just 71 minutes to defeat second-seeded Katie Boulter of Great Britain 6-1, 6-2 in Hong Kong.
Shnaider, a 20-year-old Russian, overpowered Boulter, who admitted that her busy fall tournament schedule left her playing on an "empty tank."
Shnaider broke Boulter's serve four times and didn't face a break point in the match.
Merida Open Akron
Turkey's Zeynep Sonmez crushed Ann Li of the United States 6-2, 6-1 in the final at Merida, Mexico.
Sonmez saved 3 of 4 break points in the victory and trailed only twice -- at 2-1 in the first set and at 1-0 in the second, where she then proceeded to win six straight games.
Before meeting Li in the final, Sonmez defeated Russian 17-year-old Alina Korneeva 7-6 (5), 6-2 in the semifinals.