SINGAPORE-Newly crowned world number one Angelique Kerber crushed the defending champion Agnieszka Radwanska 6-2 6-1 on Saturday to advance to the final of the WTA's end-of-season championship against Slovakia's Dominika Cibulkova.

A surprise finalist, Cibulkova booked her spot in the title match when she fought back from the brink of defeat to overhaul a weary Svetlana Kuznetsova 1-6 7-6 (7-2) 6-4 in a thriller at Singapore's Indoor Stadium. Cibulkova lost to Kerber in the round-robin phase last weekend and will have her work cut out for her as she faces the German in Sunday's final after she produced another clinical display against Radwanska.

Kerber dominated Radwanska from the outset, giving the Pole few chances to play her own game as she took control of the baselines rallies and cruised to victory in an hour and a quarter. Unbeaten in four matches this week, Kerber will go into Sunday's final as a heavy favourite as she attempts to add the WTA Finals title to her Australian Open and US Open crowns.

The pair have played each other nine times, with Cibulkova winning the first four and Kerber the last five meetings. "It's just been an incredible 12 months," Kerber said in a courtside interview. "I was here 12 months ago and I won just one match. Now I'm in the final. I'm just working on being calm. I think it'll be (a) good match... I'll have to play my best tennis to beat her again."

Voted the WTA's comeback player of the year after slumping to 66th in the world rankings in February, Cibulkova earned her place in the final the hard way. She won this month's Linz Open in Austria to qualify for the elite eight-player event then snuck into the semis on a countback after losing her first two round-robin matches, thanks in part to Kerber who beat Madison Keys in straight sets to allow Cibulkova to go through to the last four.

"There's a lot of positive emotions," Cibulkova said after beating Kuznetsova in a match that began slowly but escalated into a nail biter. The match wasn't going my way all the time but I managed to win it, even (when) I was down, even (when) she was playing really good tennis, really aggressive. I find my way to win. It was really, really tough at the end of the sets, and that's what made me win."

There were some anxious moments for the 27-year-old Cibulkova when she lost four games in a row to trail 4-2 in the deciding set but she rediscovered her best form at the perfect time and reeled off the last four games on the trot to seal victory and end Kuznetsova's own fairytale run. The oldest woman in the tournament at 31, Kuznetsova had to win the Kremlin Cup in Moscow last week just to qualify for the $7 million event. She then won two gruelling three-set encounters to reach the semis.

Battling exhaustion, she lost her final round-robin match against French Open champion Garbine Muguruza on Friday before finally running out of gas against Cibulkova. "I was just giving it all I had and that's it," Kuznetsova said. "It's not worth thinking about if I'm tired, if I'm fatigued. Whatever it is, I'm not going to make any excuses. I just did all I could, and I was a little bit short in the end."