CINCINNATI, Ohio (AFP) - Second-ranked Simona Halep will have her third chance of the season to claim the world number one spot after beating Sloane Stephens 6-2, 6-1 on Saturday (Aug 19) to reach the WTA and ATP Cincinnati Masters finals.

The 25-year-old Romanian will try to become only the 24th different woman atop the rankings by winning Sunday's final against Wimbledon winner Garbine Muguruza, who ousted top-ranked Czech defending champion Karolina Pliskova 6-3, 6-2 in the other semi-final.

"I just want to go tomorrow and play my game. If it's going to happen, great, but if not I will have more opportunities. Hopefully I can do it. I have the desire."

Halep, who hasn't dropped a set all week, has already lost twice this year playing for the top ranking, falling in the French Open final against Jelena Ostapenko and the Wimbledon quarterfinal against Johanna Konta, each time after taking the first set.

"Maybe tomorrow is my turn," Halep said.

"I have to give my best and fight and if I win it's going to be really special. It's a great opportunity. But for sure it's going to be a tough match against a Grand Slam champion.

"It's a big challenge. It's a big match."

Serena Williams had been number one before her pregnancy break earlier this year. Germany's Angelique Kerber and Pliskova have held the spot since.

Sixth-ranked Spaniard Muguruza seeks her fifth career title at the last major US Open tuneup, flipping the script on Pliskova in a rematch of their 2016 semi to reach her first final in any US event.

"I'm just happy to be in the final," said Muguruza. "I was hoping to get it and my concentration was really good. Very happy with this win."

'A STEP FORWARD'

Bulgaria's 11th-ranked Grigor Dimitrov dispatched 19th-ranked American John Isner 7-6 (7/4), 7-6 (12/10) to reach his first ATP Masters final, taking a dramatic final tie-breaker on his fourth match point.

"Patience. That's what it is," Dimitrov said. "I knew where he was going to serve but I couldn't do much on the ball. I just remained focused and used every opportunity I had."

Dimitrov, who matched his best Grand Slam showing by reaching this year's Australian Open semi-finals, seeks his third title of the season and sixth of his career Sunday against the winner of a later semi-final between Australia's Nick Kyrgios and Spain's David Ferrer.

"Tomorrow is going to be a step forward for me," Dimitrov said.

Halep, who never faced a break point, smacked a forehand winner to break for a 4-1 lead and held twice, taking the first set on a service winner then cruising to victory in 54 minutes to book her chance at a 16th career title and second of the year after Madrid in May.

"For sure it's a great feeling I'm playing in the final," Halep said. "I feel really good. I think I played my best tennis."

US 151st-ranked wildcard Stephens was in only her fourth event since returning from a foot injury that sidelined her 11 months.

'I FIGURED OUT SOMETHING'

Pliskova, last year's US Open runner-up, had won six matches in a row over Muguruza since losing their first meeting at the 2013 French Open.

"I lost to her so many times, I figured out something was going wrong," Muguruza said. "I worked hard on beating these kinds of opponents. I returned well. My shots were there. It was a gorgeous day."

Muguruza, her left thigh bandaged, broke in the first and last games of the opening set, denied Pliskova on three break points in the opening game of the second set, then broke Pliskova's final two service games for the victory.

Pliskova, who won twice Friday after a rain postponement, said she felt drained.

"I just wasn't there today at all," Pliskova said.