Williams and Bertens played on an almost empty Court Philippe Chatrier

Serena Williams remains on course to win a 22nd Grand Slam title after beating Kiki Bertens to set up a French Open final against Garbine Muguruza.

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

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

Both matches were watched by sparse crowds on another cold, grey day as Paris suffers severe flooding.

Williams, 34, is aiming to tie Germany’s Steffi Graf on 22 major singles titles, which would put her two behind all-time leader Margaret Court of Australia.

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.”

Murray was playing in his fourth semi-final at Roland Garros

Andy Murray beats Stan Wawrinka to reach his first French Open final

Andy Murray outplayed defending champion Stan Wawrinka to become the first British man to reach a French Open final since 1937.

The Scot, seeded second, won 6-4 6-2 4-6 6-2 and will face world number one Novak Djokovic in Sunday’s final.

Djokovic beat Austrian 13th seed Dominic Thiem 6-2 6-1 6-4.

Murray, 29, matches the achievement of Britain’s last finalist Bunny Austin – and will now hope to equal Fred Perry’s victory of 1936.

He also becomes one of only 10 men since the open era began in 1968 to have reached the final of all four Grand Slam tournaments.

“I’m extremely proud,” said Murray. “I never expected to reach the final here, I always struggled on the clay. I hope I can put on a good match on Sunday. BBC