"Pretty good performance from her," said Muguruza, who still has a chance to move up to No. 1 in the WTA rankings for the first time after the tournament, depending on other players' results the rest of the way.
"I was very precise with my shots," said Muguruza, who is 2-1 in her career against Halep, though the two haven't played since 2015. "I wanted to be more aggressive and take my shots. I felt pretty good out there - under control. Everything went my way."