World number one Simona Halep will play Kiki Bertens in the Cincinnati Masters final after easing past Aryna Sabalenka in the semi-finals.
Halep, 26, beat the Belarusian 6-3 6-4 to reach her second final in as many weeks.
Earlier in the day, Bertens, 26, defeated two-time Wimbledon champion Petra Kvitova for the second week in a row, winning 3-6 6-4 6-2.
"I know it is going to be a big challenge in the final," said Halep.
The Romanian - who won the Rogers Cup in Montreal, Canada, last week - has reached the Cincinnati final on two previous occasions but never won.
She broke early against Sabalenka, who beat three top 20 players en route to the last four, before breaking her opponent's serve twice more to seal the opening set.
The top seed had to deny three break points in the second set as Sabalenka levelled at 4-4 but Halep progressed through to the final on her second match point.
"It was a tough match. She was serving big - it was 110mph every time," said Halep.
"I was pretty strong and I just wanted to make her move as much as possible. I think I won this match because I was fighting until the end."
Dutch player Bertens reached her third final of the season in defeating Czech world number six Kvitova, who she beat in the Rogers Cup third round in Montreal last week.
The world number 17 won the semi-final on her first match point, and victory on Sunday would mark only her second career title.
"It was a tough match, but I'm so glad to be in the final," said Bertens.
"Over the last 12 months I've improved. We've put in a lot of work to get me more fit, to play more aggressively.
"It's working out, I'm going for my shots and serves and keeping my nerves calm."