Serena Williams is into the French Open final after a hard-fought 7-5 6-4 win against Kiki Bertens.
The defending champion will play world No 4 Garbine Muguruza in the Roland Garros finale after the Spaniard defeated Samantha Stosur 6-2 6-4 in the other semi-final.
American Williams was never at her best throughout her semi-final and frequently looked on the verge of an upset defeat to the world No 58 Bertens, but came on strong towards the conclusion of both sets.
"The first set was not simple, but she was playing so well," Williams said of Bertens. "I need to keep my calm for the final and hope the fans will be with me."
Three-time Roland Garros winner Williams arrived amid rumours of an abductor injury and, sure enough, she started slowly and was broken in the very first game.
She struggled with her mobility through the first set, but Bertens could never extend her lead, and eventually paid a heavy price after failing to make her serve count.
Facing the serve at 4-5 down, Williams struck a magnificent drop-shot to bring up break point which she duly converted. Having forced the tie-break, Williams then overcame a terrible miss at the net to narrowly edge one set ahead.
It still would not be plain sailing as Bertens again broke at the first attempt, only to concede a break straight back.
The young Dutch player always seemed to be playing crisper tennis but never had the vigour to keep Williams at bay - and the American duly broke to go 4-3 ahead.
She missed three match points against the serve before completing the job with her own service game.
Williams' bid to equal Steffi Graf's Open-era record of 22 Grand Slams will now be challenged by Muguruza, who famously gave the American an impressive run for her money during a breakthrough performance in last summer's Wimbledon final.
Since losing her first set of the tournament to Anna Karolina Schmiedlova, Muguruza has barely put a foot wrong and overpowered 2010 finalist Stosur.
Muguruza, a quarter-finalist for the last two years, looked like she might wobble when she was pegged back from 5-2 to 5-4 in the second set but two aces took her to match point and the Spaniard clinched victory when Stosur netted a forehand.
Muguruza, looking to become the first Spaniard to lift the trophy since Arantxa Sanchez Vicario in 1998, said: "Obviously it was a difficult moment and I really wanted to win so it was a combination of her playing very well and me being a little bit nervous."
"I played very well until I led 5-2 in the second set and then she stepped up a gear and I became a bit nervous.
Asked how she would prepare for the final, the Spaniard added: "Emotions are sometimes bad, you have to be calm, prepare yourself as much as you can and just play without regrets."
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