Sloane Stephens now stands in wait after winning the all-American second semi-final with Madison Keys 6-4, 6-4.

Romania's Halep has lost all three of her previous Grand Slam finals, including at the French Open in 2014 and 2017. 

She produced a dominant display today, though, breaking 2016 champion Muguruza in every one of her service games in the first set before withstanding a mini fightback in the second. 

"I think I played one of my best matches on clay," Halep said. 

"Every day I play better and that makes me happy."

Stephens repeated the result from last year's US Open final after winning the first set courtesy of a third-game break.

She led 5-2 in the second before being broken when serving for the match - only to seal victory at the second time of asking.

Rafael Nadal also moved two wins away from an 11th men's singles title after continuing his recovery against Argentine 11th seed Diego Schwartzman.

The world number one trailed 6-4, 3-5 when their quarter-final was halted due to rain yesterday, but recovered to win the next three sets 6-3, 6-2, 6-2.

Another Argentine lies in wait tomorrow in the form of Juan Martin del Potro, who beat Croatian third seed Marin Čilić 7-6, 5-7, 6-3, 7-5.

Austrian seventh seed Dominic Thiem will meet unseeded Italian Marco Cecchinato in the other semi-final.

Taiwan's Latisha Chan and Ivan Dodig of Croatia were also crowned mixed doubles champions today.

They defeated top seeds Gabriela Dabrowski of Canada and another Croat in Mate Pavic 6-1, 6-7, 10-8 to claim their maiden title as a team.

Gordon Reid beat defending champion Alfie Hewett in an all-British quarter-final of the men's wheelchair singles 6-4, 6-4 elsewhere.