Maria Sakkari, aiming to improve on her WTA Finals semifinal run last year, opened the season-ending event on Monday with a straight sets round-robin victory over Jessica Pegula.
Greece’s Sakkari, ranked fifth in the world, toppled third-ranked American Pegula 7-6 (6), 7-6 (4).
Action in the Nancy Richey Group continued later on Monday at Dickies Arena with Tunisian world number two Ons Jabeur – a finalist at Wimbledon and the US Open this year – losing to seventh seed Aryna Sabalenka.
The Belarusian player came up with a 3-6, 7-6 (5), 7-5 win to begin her campaign.
In a rematch of the WTA Guadalajara final won by Pegula last week, the American and Sakkari traded six service breaks in the opening set, Pegula twice recovering a break before Sakkari put it away in the tiebreaker.
After pocketing the first, Sakkari raced to a 3-0 lead in the second set before Pegula, who survived match points to win three times this season, broke back to trim the deficit to 3-2.
Pegula saved a pair of match points against her serve in the 12th game to force the tiebreaker, the second with a stinging backhand winner.
But Sakkari sealed it on her third opportunity when Pegula’s effort found the net.
“It’s never easy against Jess,” said Sakkari, who improved to 4-2 against the American. “She’s an amazing player. She’s very confident right now. I knew it was going to be extremely tough but I fought hard and trusted my game.
“I was well-rested compared to the previous match. I’m very excited to start with a win here.”
Buy an annual Scroll Membership to support independent journalism and get special benefits.
Our journalism is for everyone. But you can get special privileges by buying an annual Scroll Membership. Sign up today!