Iga Swiatek extended her winning streak to 31 with a 6-3, 7-5 defeat of Danka Kovinic in the third round of Roland Garros, though the No.1 seed had to scrap to put away a dogged opponent over 1 hours and 30 minutes.

Swiatek, the champion here in 2020, has now reached the second week in all four of her Roland Garros appearances, and she has won 17 of her 19 matches at the tournament.

Roland Garros: Scores | Order of play | Draw

Her active winning streak, which stretches back to February and encompasses titles in Doha, Indian Wells, Miami, Stuttgart and Rome, is the fourth-longest of the 21st century. The 20-year-old Pole is one win away from tying Justine Henin's 32 in 2007-08; a final would equal Serena Williams's 34 in 2013, and a title would put her level with Venus Williams's 35 in 2000.

No.95-ranked Kovinic, the first Montenegrin to reach the third round at Roland Garros, delivered a valiant performance. Having never gone beyond the second round of a major in 17 main draws prior to this year, Kovinic has now made the third round of both of this year's Slams.

Match management: By the first changeover, Swiatek led 3-0 but needed six break points and 13 minutes to capture the initial break.

Swiatek led 4-2, 40-0, but let that lead lead slip amid a flurry of loose forehands that allowed Kovinic to get back on serve. But Kovinic immediately relinquished her momentum with four unforced errors to gift the break back to Swiatek.

In the second set, Swiatek built a 4-1 double-break lead, only for her forehand to abandon her again. A cascade of errors from that wing opened the door again for Kovinic, who seized her opportunity. The former World No.46 ran off four straight games, conjuring up several superb drop shots along the way.

As in the opener, the closing stages of the set saw Swiatek steady herself while Kovinic relapsed into error. Down 5-4, Swiatek delivered two solid service games around a timely break of the Kovinic serve to advance to the fourth round. In total, she had committed 23 unforced errors to only 13 winners -- but had managed to summon her better tennis when it had been needed.

In Swiatek's words: "For sure I felt like she used my power in some moments so I had to adjust a little bit more to what she was playing, and for sure played a little bit more smart.

"I changed the tactics in second set a little bit to play less risky, but then I did some mistakes. I lost my breaks. I'm not perfectly happy with that, but overall I'm happy with the performance, and that I came back in the second set."

Swiatek's Roland Garros reading: " I finished a few days ago "21 Lessons for the 21st Century" [by Yuval Noah Harari]. And then I read [Agatha Christie's] "Murder on the Orient Express" in like two days. And now [Alexandre Dumas'] "The Three Musketeers."

"'21 Lessons' was a hard one to digest because it's about basically the purpose of life. I took a lot in terms of broadening my horizons, because the author is pretty thoughtful about some things, and he provokes some ideas I didn't even think about. But also kind of typical to what science fiction movies show us.

"It was pretty nice to educate myself a little bit more. But on the other hand, it was kind of about the future, so you never know what's gonna happen, and these were his ideas so I don't know how to really trust in that. But I'm going to read also other book of his, so I'm going to see what I take from those ones as well."

Zheng Qinwen advances, Begu halts Jeanjean

Swiatek will next face 19-year-old Roland Garros debutante Zheng Qinwen, who reached the fourth round of a major for the first time after Alizé Cornet retired trailing 6-0, 3-0 due to a left thigh injury.

The No.74-ranked Zheng broke Cornet twice from game point down to take a 3-0 lead, dominating play with both her raw power from the baseline and a deft touch on the drop shot. The Frenchwoman, who wore heavy strapping on both thighs, was increasingly hampered as the match drew on. Cornet won only six more points in the next six games before being forced to call it quits.

Romania's Irina-Camelia Begu returned to the fourth round at Roland Garros for the first time since 2016, defeating French wildcard Leolia Jeanjean 6-1, 6-4. Ranked No.63, Begu withstood a surge from Jeanjean in the second set to close out the win after 1 hour and 25 minutes. Despite generating more break-point chances, 11 in total, the 26-year-old Frenchwoman was able to break Begu just once in the match. Begu finished the match with twice as many winners as Jeanjean, while keeping a cleaner sheet, hitting 21 unforced errors to 27.

Begu, who previously reached the fourth round at the 2015 Australian Open and 2016 French Open, will next face either No.11 seed Jessica Pegula or 2021 semifinalist Tamara Zidansek for a spot in her first major quarterfinal.