French Open champion Gauff did not do too much wrong in the opening set but Sabalenka excels in tie-breaks, having won 22 of the 24 breakers she has played this year.
Gauff’s serve, which has been problematic in recent times, held up extremely well in the first set – with 72% of first serves in, 62% of first-serve points won and 70% of points won behind her second serve.
However, she failed to serve out the opener at 5-4 up before her first double fault of the match gifted four-time major singles champion Sabalenka two set points in the tie-break.
On the other side of the net, Sabalenka demonstrated the full range of emotions as she twice battled back from a break down; frustration after several points lost, despair after sending a backhand volley wide during the tie-break and then celebration as she thrashed a powerful forehand winner to clinch it.
Sabalenka quickly moved 4-0 up in the second and, despite briefly giving back one of her two breaks of serve, she served out victory to stay on course for a first WTA Finals title.
Sabalenka is into the semi-finals for a fourth successive year but has only reached the final once, losing to Caroline Garcia in 2022.
