"I believe I have the game to win".
Halep feels better equipped to finally break her duck in Paris.
Sloane Stephens maintained her ideal record against fellow American Madison Keys as she blazed into the French Open final with a 6-4 6-4 win on Thursday in a repeat of last year's U.S. Open final.
"But it's emotional to be making this speech as a victor".
"It's been unbelievable here for me", said Stephens.
"When I was down a break in the second set I just tried to relax and enjoy the match".
Half an hour later 1-0 had become 6-1 and the challenge of Muguruza, who would have taken over at the top of the rankings with a victory, appeared to be fading fast.More news: Harry Kane Signs A Six-Year Deal With Tottenham Hotspur
The 25-year-old, who was ranked 957 in the world less than a year ago after her injury woes, was using her bigger forehand to good effect as Halep struggled to make any inroads into her opponent's serve.
But Keys, who made 23 unforced errors in the first set, hit back hard and set up a break point at 3-2, only for Stephens to save it with a service return victor. However, Halep is not reading too much into her impressive record against Stephens.
After a timid start, Stephens found her rhythm and took control of the opening set by breaking in the third game with a forehand victor down the line.
The Romanian knows better than anyone how Grand Slam finals can turn though after her 2017 heartbreak against Ostapenko, and she broke back to love to the delight of the crowd. But Stephens has found it tough going against Halep, who has won five of their seven previous matches - including the past four.
A nervous start from the Spaniard was immediately pounced upon by Halep for a break in the opening game.
Keys slipped two breaks down in the second but although she pulled one back Stephens served out for the match.