Garbine Muguruza believes Simona Halep will break her grand slam duck in the final of the French Open, the world number one having proved too strong for the Wimbledon champion in their semi-final.

Halep outclassed Muguruza 6-1 6-4 at Roland Garros on Thursday to book her second straight appearance in the French Open final.

Although the Romanian has lost on her three previous appearances in grand slam finals, Muguruza thinks she will break her duck on Saturday – when she faces Sloane Stephens.

"It's her third finals in Roland Garros, and she has a great level," Muguruza told reporters.

"She played very well against me. I don't know what rival she will have in the finals. But apart from being number one, she's also the favourite for this tournament.

"I think that today I had an opponent who is playing very well, very few free points, and my play was not so effective as in the previous matches.

"It's the match in Roland Garros where I played the worst. It was an important match, and she was aggressive right from the start. She played very well right from the onset, and that's the result."

World number three Muguruza now turns her attention towards defending her Wimbledon title.

"I will play a tournament before to prepare myself," the Spaniard said. "Well, there are just two tournaments on grass, and I will try to be in shape for Wimbledon. It's a very difficult surface. I was very successful on grass, so let's see what happens. 

"Grass is very unpredictable. I'm always going there and let's see what happens this year. So, you know, I feel overall that these two weeks have been great, so of course it pumps up a little bit the energy to keep it up. So, yeah, I'm excited for the grass.

"I feel like grass and clay, there are differences that you can use. So I'm happy to change the surface, because I think in hard court it's just everybody plays good. Everything, it's more equal.

"So when I can play on clay court and grass, I don't know, I feel excited that everybody has ups and downs or you see a little bit more. I think it's going to be interesting."