Aryna Sabalenka said her semi-final victory over Iga Swiatek at the Cincinnati Open is firmly in the past as she looks towards ending her US Open preparations with a title.

Sabalenka, who has reached her fifth Tour-level final of the year, triumphed in straight sets over Swiatek to set up a showdown with Jessica Pegula in Ohio.

The Belarusian had lost her last three matches against Swiatek, but snapped that run to reach her first Cincinnati Open final at the fourth attempt. 

"It was a brilliant performance from me. But I just want to focus on staying in the moment and giving my best tennis every time I'm on the court," Sabalenka said. 

"I try to stay calm, confident and aggressive on the court. That definitely gave me a lot of confidence, going into the US Open.

"But that's already in the past, if I focus on this win, it'll stay in the past. I'm really happy with the win."

Having taken a 5-1 lead, Sabalenka saw seven match points saved by Swiatek in the seventh game, squandering two more shortly after as the Pole threatened to produce an unlikely turnaround. 

But Sabalenka was able to get over the line at the 10th attempt, saying that period was the toughest moment of the encounter. 

"I kept telling myself 'she's the world number one, she's going to keep fighting and doing her best'," Sabalenka said.

"You have to stay aggressive. You have to put pressure on her.

"You have to play your tennis and try. That was my mentality in the tough moments.

"That was definitely the toughest moment of the match. When I'm in the zone, what thoughts do I have? There are no thoughts. Just about the tennis.

"About the next ball coming. Just about hitting and trying to make the right decisions. You have nothing in your head."