American teenager Coco Gauff is into the quarterfinals of the French Open for the second year running after a 6-4, 6-0 victory over Elise Mertens on Sunday.

"I think today even though I had some tough moments I was able to tough it out. I really do feel like I'm progressing with each match," Gauff said after the match.

Gauff's second career win against the Belgian was less complicated than her first: a three-set comeback last year on the grass in Eastbourne from 6-0, 2-0 down.

The 18th seeded American will next face compatriot Sloane Stephens at a major for the second time in the span of a year. Trailing No. 23 seed Jil Teichmann with the Swiss serving at 2-0, 40-15, the 2017 US Open winner won 12 games in a row to reach the quarterfinals at Roland Garros for a third time.

The two Americans played last summer in the second round of the U.S. Open, and that match was won by Stephens, 6-4, 6-2.

Meanwhile, last year's U.S. Open runner-up Leylah Fernandez defeated No. 27 Amanda Anisimova 6-3, 4-6, 6-3 in a fourth-round clash of under-21 talent at Roland Garros. The 19-year-old Canadian reached her second Grand Slam quarterfinal and first in Paris in 1 hour and 54 minutes.

Next up for her is another left-hander Martina Trevisan, who squeaked past Aliaksandra Sasnovich 7-6(10), 7-5 in 1 hour and 59 minutes to extend her winning streak to nine matches.

"Yes, today's match was a very hard match, an incredible match for the both of us," said Fernandez. "I think we brought a high level. I'm just glad that today I was able to fight through some difficult moments and just enjoy the game as much as possible and just to have another opportunity to play in Philippe Chatrier. It was just an amazing atmosphere and it was a great feeling for me."

(With input from WTA Official)