Halep and Svitolina will square off Saturday night at Aviva Centre after winning their rain-delayed quarter-final matches earlier in the day.
"I thought she started off really strongly and she was attacking and playing really, really well", Wozniacki said.
She jumped into a 3-1 lead in the second set before allowing Stephens to rally back.
Halep saved a match point as she broke for 5-1 in the second set but Svitolina was not to be denied in the next game, sealing her passage through to the final as the former fired a forehand into the net. "It's really hard to get to Cincinnati and there's no tickets, so I needed to get them".
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Wolfe was a key player on the Broncos' Super Bowl 50 team as he was a force against the run and as an inside pass rusher. Denver's defense was already worse for wear even before Wolfe's injury.
Korean tensions keep yen near eight-week highs
Pacific island territory of Guam in an unusually detailed threat that further heightened tensions with the United States. USA crude (CLc1) was unchanged at $48.59 per barrel and Brent (LCOc1) was last at $51.84, down 1.63 percent on the day.
Thunder to play regular-season game in Mexico
The event itself is a celebration of the NBA's games in Mexico City. "This is a competitive market, well over 20 million people". Brooklyn will be considered the home team for the game and it will also be hosting the Oklahoma City Thunder on December 7th.
Asked if the 0-5 record in finals this year weighs on her mind, Wozniacki chuckled and said, "No, not unless I get asked about it". I have many tournaments ahead.
After the match, Halep struggled to explain what went wrong.
"I was just trying to play my game and I was very happy to win".
"I just tried to stay steady, tried to take the ball on the rise and try to stay aggressive when I could and keep my serves aggressive too". But she's a very consistent player.
"She's having a good year as well - injury free and playing really well", Svitolina said. "But, you know, maybe that's also the key why it's been going so well, because I just walked in and I was more relaxed about the whole thing".