Muguruza picked up where she left off after shocking World No.1 Serena Williams in the second round by beating Anna Schmiedlova in the third round. The 20-year-old Spaniard was playing a Grand Slam fourth round match for the second time, having also gotten that far at this year's Australian Open.
A wildcard into this event, Parmentier was playing her first Grand Slam fourth round match, with her 13-match losing streak in WTA main draw matches coming into Roland Garros long forgotten.
Though eight games, it was 4-4, with each player having one break. But then Muguruza broke for 5-4 and held for 6-4. Parmentier had lost the opening set but won the match in each of her previous matches this fortnight, but it was not to be this time. At 1-1 in the second set, Muguruza broke, held and broke again en route to a comfortable second set win and a 6-4, 6-2 victory - making her the only player on the top half of the draw yet to surrender a set.
By The Numbers
Muguruza won 23 of 30 first serve points, while Parmentier made good on just 23 of 45. Muguruza was also 10 of 14 at the net compared to two of six for Parmentier. Finally, Muguruza had eight more winners than unforced errors, while Parmentier had 12 more unforced errors than winners.
"I feel amazing," Muguruza said. "I didn't expect this. It's a present. I'm very happy with what I have done so far, but I want to continue. I still have more matches, so I'm looking forward to my next round."
"It has been an unbelievable week," Parmentier said. "Of course I'm slightly disappointed, but there are many positive lessons that I can draw from this match. I enjoyed the tournament and leave with a lot of positives in my mind. Even though I was defeated today, it has been great."
"I know it's going to be a tough match," Muguruza said. "She's a very, very good player. I have nothing to lose. I'm going to do my best and try to enjoy it as much as I can. I'm going to rise to the challenge. I'll walk onto court with the mindset that will allow me to win, as I always do for all my matches."