Jessica Pegula and Aryna Sabalenka produced dominant displays to advance to the WTA Finals semi-finals, overcoming Jasmine Paolini and Coco Gauff respectively.
Pegula, who had impressed despite losing to Sabalenka earlier in the week, overwhelmed an unwell Paolini 6-2 6-3, with her forehand particularly effective.
Sabalenka faced a sterner test against Gauff, who started brightly and led 4-2 with break points in the first set. But the world No 1 saved them, fired three consecutive aces, then edged a tense tiebreak before racing through the second set 6-2.
Gauff showed improvement on serve and forehand but could not sustain it. Sabalenka won her group with a perfect record, while Pegula also advanced.
The semi-finals will see Pegula face Elena Rybakina and Sabalenka meet Amanda Anisimova. Sabalenka expressed delight at Anisimova's return to form, and said she relished the challenge of playing at her best under pressure.
