Montreal - Serena and Venus Williams will clash in the semi-finals of the Montreal WTA tournament after the American sisters battled through tough three-setters in the quarter-finals on Friday.
World number one Serena outlasted Caroline Wozniacki to clinch a 4-6, 7-5, 7-5 victory, while Venus also came from a set down to end the run of Spanish 14th seed Carla Suarez Navarro, the third round conqueror of Maria Sharapova, 4-6, 6-2, 6-3.
This is the 25th meeting between the two as Serena will take a 14-10 career lead in into Saturday's match. The 32-year-old has won their last five meetings as Venus has failed to beat her younger sister since a three-set victory in Dubai five years ago.
Despite her recent success, Serena said Friday she dreads playing her sister.
"I definitely don't like playing her," said Serena, who won their most recent match 6-1, 6-2 last year in Charleston. "I think I've lost to her more than anyone on the tour. Definitely not a fun match.
"But she's tough. She has a great serve. She runs every ball down. She has a great backhand. She hits winners off the forehand."
Serena also said Friday that she is surprised to still be playing competitively in her 30s.
"I definitely didn't see myself playing tennis at my age," Serena said. "I just thought I would have been gone doing other things. But it just so happens that I love to play, I love to compete. I just can't give it up."
Venus, who has had health troubles the last few years, said she will be better prepared for Saturday's semi-final.
"I'll be able to make it more competitive."
She told reporters Friday that the night before a tough match she likes to dance for 30 minutes because it relaxes her.
"Not at a club. No, I just do a little jazz and a little ballet," Venus said. "I'm not great, but I love to dance. I'll just dance a little and see what happens. Just a little bit and try and relax.
"I can't get into the details. It's like Fame. Have you ever seen that?"
The other semi-final will see third seeded Agnieszka Radwanska face Russian Ekaterina Makarova.
Serena, who lifted her third Canadian crown last year when the tournament was held in Toronto, battled back from a set and a break down to claim victory over Wozniacki in two hours and 41 minutes.
"When you play someone like Caroline or other opponents, you know your match might be a little longer than normal," said Serena, who extended her career head-to-head record over the 13th-ranked Dane to 7-1.
"You go in there thinking, this is not going to be routine. You have to be ready."
Wozniacki, a former world number one who is seeded 11th, claimed her only victory over the US star in the quarter-finals at Miami in 2012.
Wozniacki had been riding an eight-match winning streak, including a title in Istanbul in July.
"It was really the small things that I did out there today," added Wozniacki.
"She came up with quite a few big serves when she needed to. It could have gone both ways."
Serena claimed her fourth title of the year at Stanford on Sunday, but she has disappointed in the majors this year, failing to add to her cache of 17 Grand Slam titles.
She'll get a last chance of 2014 to do so at the US Open, which starts in Flushing Meadows on August 25.
As she has in many of her recent matches, Serena got off to a slow start against Wozniacki and the Dane was soon up 6-4, 4-2.
With the aid of an improved serve -- which yielded a total of 15 aces in the match, Serena began to assert herself.
"I am definitely fit," Serena said. "I feel like I am ready to go the long haul. I needed to feel that and get some three-set wins under my belt."
Wozniacki twice recovered a break in the third set before Serena finally closed out the match.
Radwanska breezed past eighth seeded Victoria Azarenka 6-2, 6-2 while Makarova slipped past American qualifier Coco Vandeweghe 6-1, 4-6, 6-1.
Results on Friday from the fifth day of the WTA Montreal tournament (x denotes seed):
Serena Williams (USA x1) bt Caroline Wozniacki (DEN x11) 4-6, 7-5, 7-5
Venus Williams (USA) bt Carla Suarez Navarro (ESP) 4-6, 6-2, 6-3
Ekaterina Makarova (RUS) bt Coco Vandeweghe (USA) 6-1, 4-6, 6-1
Agnieszka Radwanska (POL x3) bt Victoria Azarenka (BLR x8) 6-2, 6-2