For Worth, United States: Aryna Sabalenka beat Jessica Pegula 6-3, 7-5 on Friday to keep her hopes alive at the WTA Finals, where her chance at a semi-final spot still depended on the outcome of the day's second round-robin match.
Seventh-ranked Sabalenka did her part with the victory over third-ranked American Jessica Pegula.
But second-ranked Tunisian Ons Jabeur could snag the second qualifying spot from the Nancy Richey Group with a straight-sets victory over fifth-ranked Maria Sakkari of Greece.
Sakkari is assured of finishing top of the group, and will face either France's Caroline Garcia or Daria Kasatkina in the final four.
With so much on the line, Sabalenka was dialed in from the start.
"I definitely was happy with my serve for the (first) half of the match," Sabalenka said. "I'm just happy that I was really focused from the beginning to the end and I was able to finish this match in two sets."
Sabalenka, who improved to 4-1 against Pegula, took charge early and took full advantage of four first-set double faults from Pegula.
The second set was a more tightly contested affair, Pegula quickly erasing an early break as Sabalenka suddenly found herself struggling on serve.
Despite seven double faults in the second set, Sabalenka managed to keep it close and broke for a 5-3 lead to pile the pressure back on Pegula.
Pegula, who secured her spot in the elite season-ending event with her triumph at Guadalajara in October, responded with a service break of her own and leveled the set at 5-5, Sabalenka digging deep to win the last two games and polish it off in two sets.
