Elina Svitolina battled her way into a first WTA Finals title-decider after being pushed all the way by Kiki Bertens in Singapore.

Svitolina is just one victory away from claiming the biggest crown of her career following a hard-fought 7-5 6-7 (5-7) 6-4 win on Saturday.

The Ukrainian said she is on a mission to silence the "haters" this week and has surely already achieved that with four victories out of four.

Bertens, only making her debut in the season-ending tournament because Simona Halep was ruled out with a back injury, caused Svitolina plenty of problems with her aggressive approach, but a mammoth 63 unforced errors cost the eighth seed.

Svitolina was more composed and defended superbly throughout an absorbing contest which took two hours and 38 minutes to settle, sealing a place in the final against Karolina Pliskova or Sloane Stephens.

Sixth seed Svitolina was rewarded for a positive start when she secured the first break, Bertens slapping an inside-out forehand wide to go 3-1 down.

The world number nine hit straight back with vigour, applying the pressure with venomous forehands to get back on serve, but a series of errors from the baseline gifted Svitolina another break - and the opening set.

Bertens threw her racket down in fury following one of those unforced errors, but regained her composure to take a 2-0 lead in the second set following some instructions from her coach Raemon Sluiter.

A resilient Svitolina saved four break points before breaking back to level at 5-5, only for Bertens to edge a tie-break which included seven mini-breaks, a rasping return taking it to a decider.

The Dutchwoman was furious with herself once again when she steered an attempted drop shot into the net to give Svitolina a break, yet responded impressively again to win a Svitolina service game which lasted over 13 minutes.

A couple of poor backhands handed Svitolina another break for a 2-1 lead and the unpredictable Bertens was unable to find a way back, the world number seven saving two break points before finally grinding it out.

STATISTICAL BREAKDOWN

Svitolina [6] bt Bertens [8] 7-5 6-7 (5-7) 6-4

WINNERS/UNFORCED ERRORS

Svitolina – 12/36
Bertens – 41/63

ACES/DOUBLE FAULTS

Svitolina – 3/2
Bertens– 7/5

BREAK POINTS WON

Svitolina – 5/8
Bertens– 3/9

FIRST SERVE PERCENTAGE

Svitolina – 59
Bertens – 60

PERCENTAGE OF POINTS WON ON FIRST/SECOND SERVE

Svitolina – 66/56
Bertens – 69/52

TOTAL POINTS

Svitolina – 114
Bertens – 111