Serena Williams to face Garbine Muguruza in French Open final

Williams and Bertens played on an almost empty Court Philippe Chatrier

Serena Williams is aiming to level with German Steffi Graf on 22 major singles titles as she takes on Garbine Muguruza in the French Open final on Saturday.

The American top seed was well below her best, but beat unseeded Dutch player Kiki Bertens 7-6 (9-7) 6-4 in the semi-final.

Spanish fourth seed Muguruza impressed in a 6-2 6-4 win over former finalist Sam Stosur of Australia.

"If I get there it will be great," said Williams, 34.

"The only thing can I do is just play to win the tournament and that's it."

If Williams lifts the title, it would put her two behind all-time leader Margaret Court of Australia.

Muguruza is through to her second Grand Slam final

Williams out of sorts but into final

Defending champion Williams had made a host of errors in her quarter-final and was unusually inconsistent again as she faced an opponent making her Grand Slam semi-final debut.

Both women went into the match with injury doubts - Bertens struggling with her calf and Williams reportedly playing through a thigh problem.

Bertens, ranked 58th, had plenty of chances in the first set against a sluggish Williams, earning seven break points and two set points, but Williams came back from 4-2 down to clinch it in an unpredictable tie-break.

Two dreadful volleys, one of them on set point, illustrated Williams' lack of form but experience dragged her through, and she came back from a break down to take control of the second set.

Muguruza makes short work of Stosur

Saturday will see a repeat of last year's Wimbledon final after Muguruza swept aside 2010 runner-up Stosur on a barren Court Suzanne Lenglen.

The 22-year-old, who was born in Venezuela, raced into a 4-0 lead and took the opening set in 32 minutes.

A sixth double-fault by Stosur gave Muguruza a 5-2 lead in the second set but she faltered with victory in sight, playing a poor service game, before closing it out at the second opportunity.

Muguruza is the first Spanish woman since Conchita Martinez in 2000 to reach the final in Paris.

"Emotions can sometimes be bad when you make a final," said Muguruza. "Sometimes you just have to stay calm, prepare yourself as best you can and play with no regrets."

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