MONTREAL -- It will be Simona Halep versus Madison Keys in the final of the US$2.4 million women's Rogers Cup.

Halep, the fifth seed, defeated second-seed Angelique Kerber of Germany 6-0, 3-6, 6-2 in a semifinal Saturday at Uniprix Stadium to reach the Rogers Cup championship game for a second year in a row. The Romanian dominated the first half, saw Kerber find momentum midway through the second set, then took over again in the third.

The 10th-seeded Keys needed only 50 minutes to end the Cinderella story of qualifier Kristina Kucova with a 6-2, 6-1 victory. Kucova, the world's 112th-ranked player, had knocked off two seeded players as well as local favourite Eugenie Bouchard enroute to the semifinal in her career-best performance.

Halep has won two of three matches against Keys, including in the round of 16 in Wimbledon in June.

"She hits the ball very strong," Halep said of Keys. "Her serve is good.

"It will be not like today, with many rallies. In Wimbledon, the points were shorter. So I expect that I will not have a good rhythm because she can hit a winner and you don't see the ball. But she can miss sometimes. I have to stay focused for every ball and not to be upset like today."

Her match with Kerber was a back and fourth affair, with only a few games where both players looked sharp at once.

In last year's final in Toronto, Halep retired in the third set with a heat-related illness, handing the win to unseeded Belinda Bencic of Switzerland. Her march to that final included a win over Kerber. Halep has beaten Kerber all four times they met on hard courts, but lost their two matches on other surfaces.

There were more empty seats than usual for a semifinal on centre court, but a large contingent of flag-waving Romanian fans turned out to back Halep.

Kerber, the reigning Australian Open champion, seemed lost in the opening set, losing her first two service games thanks to an erratic serve that included three double faults. More than once the left-hander made gestures of frustration on court after misfired shots.

She gave up another break point on a double fault to fall behind 2-3 in the second set, but then broke straight back. It was Halep making angry swings that didn't quite connect with the ground after a shot into the net as Kerber held service for 4-3.

Kerber won six games in a row, including a service break to start the third set, but then Halep took over again with a break to tie it 2-2 and go on a run of six consecutive game wins to end the match.

"In the second set when I lost the serve at 3-2, I was a little bit disappointed," said Halep. "Also the nerves were very big.

"I don't know why, but I couldn't manage that moment and I can say I gave up a little bit mentally. But then in the third set, I said that I have to calm down, to just go and play like I did in first set -- aggressive, to open the court, to try to finish the points with winners.

In the final game, Kerber fought off four match points, but then saw her final shot hit the net cord, move sideways and drop perhaps a centimetre outside the line.

"She was playing more consistently than me the whole match," said Kerber. "Not like me, with a lot of ups and downs.

"I think the tournament was good for me because I had a lot of tough and close matches during the week. It was the first tournament on hard courts, so it's good to have a lot of matches before going to Rio. I'm actually feeling good. I'll take the positive things and look forward to playing at the Olympics."

Kucova, 26, will break into the top 100 in WTA rankings for the first time in her career with her Rogers Cup performance. The $120,140 prize money for reaching the semifinals was $40,000 more than she had earned in the last six months on tour.

Halap took a rest break and was right back out on the court with compatriot Monica Niculescu to win their doubles semifinal 6-3, 2-6 (10-6) against the Slovakian duo of Andreja Klepac and Katarina Srebotnik. Halep can become the first to win the singles and doubles in the same year since Martina Hingis in 2000. Others to have done it include Arantxa Sanchez Vicario in 1994 and Martina Navratilova in 1982.

"Actually, when I started the tournament, I said with the prize money from doubles I will go shopping," she said with a laugh. "Now I have enough, so I will enjoy it.

"Maybe that's why I kept winning."