Petra Kvitova extended her winning streak to 10 matches as she beat Czech compatriot Karolina Pliskova in straight sets to book her place in the Madrid Open final.
Fresh from victory at the Prague Open last week, Kvitova twice battled back from a break down in the opening set to eventually claim a 7-6 (7/4) 6-3 win in one hour and 43 minutes.
Pliskova had made a storming start, breaking her opponent in the opening game of the match and later establishing a second break advantage before being forced into a tie-break.
There the sixth seed capitulated, serving successive double points to hand the first set to Kvitova,
The former Wimbledon champion was in no mood to give up her advantage, breaking Pliskova immediately at the start of the second set and again when Pliskova served to stay in the match at 5-3 to wrap up victory.
In the final, Kvitova will face unseeded Dutch player Kiki Bertens, who continued her superb form in the tournament with a 6-2 6-2 win over Caroline Garcia.
Bertens, who beat world number two Caroline Wozniacki in an earlier round, dominated proceedings throughout to book her place in the biggest final of her career.
Bertens told wtatour.com: "I'm in the final now, and I have a chance tomorrow but it's going to be really, really tough.
"Right now I'm just really happy about my performances through the whole week. I'm just trying to go there tomorrow and do the same, and we will see."