Sloane Stephens stands on the brink of the last four at the WTA Finals after coming out on top in an almighty battle with Kiki Bertens.

Bertens would have qualified for the semi-finals with a victory after Angelique Kerber beat Naomi Osaka in the first match in Singapore on Wednesday.

Yet Stephens ensured it is all to play for in the Red Group with one round-robin match remaining by coming from a break down in the final set to win 7-6 (7-4) 2-6 6-3.

Both debutants won their first-ever contests in the season-ending tournament and still have their fate in their own heads, with group leader Stephens facing Kerber on Friday and Bertens up against Osaka.

Bertens, a late replacement for the injured Simona Halep, had Stephens in trouble with her aggressive approach after losing the first set, but 47 unforced errors proved to be costly for the Dutchwoman.

Stephens knew a straight-sets win would put her through and the 2017 US Open champion got off to a great start, breaking when Bertens missed an inside-out forehand as she breezed into a 3-0 lead.

Bertens warmed to the task, mixing up her approach and forcing mistakes from the American, who was broken for a second time after taking a 4-2 lead.

It was Bertens coughing up the unforced errors in the tie-break, though, another uncontrolled inside-out forehand giving Stephens the opening set.

The eighth seed responded by winning the first two games of the second and led 5-1 as Stephens failed to contain the world number nine, who broke again to take it to a deciding set.

Stephens hung in there and won four consecutive games from 2-0 down in the final set, Bertens running out of steam as the fifth seed took control, sealing victory with a deft drop shot.

 

STATISTICAL BREAKDOWN

Stephens [5] bt Bertens [8] 7-6 (7-4) 2-6 6-3

WINNERS/UNFORCED ERRORS

Stephens - 18/37
Bertens - 24/47

ACES/DOUBLE FAULTS

Stephens - 0/3
Bertens - 2/8

BREAK POINTS WON

Stephens - 7/13
Bertens - 7/9

FIRST SERVE PERCENTAGE

Stephens - 78
Bertens - 61

PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE

Stephens - 50/47
Bertens - 66/34

TOTAL POINTS
Stephens - 92
Bertens - 101