French Open 2021: Iga Swiatek advances to quarterfinals with win over Marta Kostyuk

The fourth round of the 2021 French Open continued on Monday with spots in the quarterfinal on the line. Young American star Coco Gauff started the day with another notable achievement while on the men's side, Novak Djokovic looked to defend his top seed.

Follow along below for updates on the fourth round of French Open action.

Iga Swiatek advances to quarterfinals

In a women's bracket where the top seeds have fallen every day, Iga Swiatek remains. Swiatek advanced to the quarterfinals with a win over Marta Kostyuk on Monday.

Swiatek defeated Kostyuk in straight sets, winning 6-3 and 6-4.

With the win, Swiatek is the highest seed on the women's side still in the French Open. Swiatek, who is ranked No. 8, entered the day as the second-highest seed left on the women's side, but American Sofia Kenin — ranked No. 4 — fell to Maria Sakkari on Monday.

Swiatek will take on No. 17 Maria Sakkari on Wednesday in the quarterfinals.

Rafael Nadal makes quick work of Jannik Sinner

Rafael Nadal got off to a sluggish start against Jannik Sinner in the fourth round of the French Open on Monday, but approached perfection by the end of the match.

Nadal rallied from the tough start to defeat Sinner in three sets Monday. The win pushed Nadal into the quarterfinals, where he'll take on Diego Schwartzman on Wednesday.

Things looked shaky for Nadal early. He fell behind Sinner 5-3 in the first set, but got things together, eventually taking the set 7-5. From there, Nadal cruised, taking out Sinner 6-3 in the second set and 6-0 in the final set.

Following the match, Nadal revealed a crucial change he made while trailing in the first set. Nadal said he was playing Sinner too defensively at the start of the match and was lucky to make that change and turn things around before Sinner took a commanding lead.

Nadal — ranked No. 3 — will face a shift challenge against Schwartzman — ranked No. 10 — in the semifinals. A win over Schwartzman could set up a Nadal-Djokovic match in the semifinals.

Novak Djokovic advances in dramatic comeback

Novak Djokovic is in the French Open quarterfinals for a 12th consecutive year after his opponent, Lorenzo Musetti, retired in the fifth set because of injury. He appeared to suffer a groin injury and had trouble moving around the court in the final set.

Djokovic advanced 6-7 (7), 6-7 (2), 6-1, 6-0, 4-0.

Musetti, a 19-year-old Italian playing in his first Grand Slam, took the first two sets over the No. 1 ranked tennis star. They took 2:21 to complete with Musetti one set away from an upset victory. He hit 25 winners in those sets and worked his backhand to the lead.

Djokovic stormed back and won the next two sets in a quick 43 minutes. He took 28 of 30 points from 3-1 in the third set to a 4-0 lead in the fourth set.

In total he's now come back five times to win from two sets down and is 34-10 in matches that go a full five sets, per Christopher Clarey at the New York Times.

Djokovic was so on point down the stretch he won a baseline rally in which he hit a shot while lying on his side.

The next test for the reigning Australian Open winner is ninth-seeded Italian Matteo Berrettini in the quarterfinals.

Coco Gauff reaches first Grand Slam quarterfinal

Coco Gauff, the 17-year-old American who broke out at Wimbledon in 2019, is into her first Grand Slam quarterfinal after defeating Ons Jabeur 6-3, 6-1 in a quick 53 minutes. The two are both former junior Roland Garros champions.

She is the youngest American to reach a Grand Slam quarterfinal since Venus Williams did it at the 1997 U.S. Open. Williams reached the final, where she lost to world No. 1 Martina Hingis. Gauff is the youngest to reach a Grand Slam quarter since 2006.

Gauff, seeded No. 24, will meet unseeded Barbora Krejcikova, ranked No. 33 in the world, in the quarterfinals.

The teenager soared into her first quarterfinal with ease and did not face a break point in the match. She also didn't record a double fault, a notable feat given her difficulties serving in recent matches. Gauff lost only nine points on her serve through the entire match. She is now 16-3 (.840) on clay this season.

Americans Stephens, Kenin struggle

Barbora Krejcikova advanced with a strong 6-2, 6-0 win against American Sloane Stephens, the 2018 French Open runner-up.

Krejcikova is a former No. 1 in doubles and won two Grand Slam titles with Katerina Siniakova. The duo play in the doubles quarterfinals on Tuesday.

Fellow American Sofia Kenin also struggled in the fourth round. She fell to Maria Sakkari, 6-1, 6-3. It's the first time in the Open Era a Greek woman reached the quarterfinals of of a Gram Slam.

The fourth-seeded Kenin was runner-up at the 2020 French Open.

Dylan Alcott wins third straight quad wheelchair singles title

The title remains with Dylan Alcott.

Alcott won his third consecutive French Open title in men's quad wheelchair singles on Tuesday with a 6-4, 6-2 win against the 21-year-old Sam Schroder.

It's the 13th Grand Slam title for the 30-year-old Australian. Alcott thanked his team, his family and his girlfriend and sent good wishes to those back in Melbourne on COVID-19 lockdown orders. He made a reference to the future.

"I don't know how many more I have got left in me," Alcott said, via ABC News Australia.

Alcott is a giant in tennis and is the only man to Grand Slam in a calendar year in the men's doubles quad wheelchair event. He has seven consecutive wins and counting at the Australian Open in singles, two total at the U.S. Open and one at Wimbledon in 2019.

He was outspoken last summer when the U.S. Open attempted to hold its Grand Slam without wheelchair events during the height of the COVID-19 pandemic. He called it "disgusting discrimination" when it was announced. The organizers restored the standard competition in what Alcott said was a "massive sign of progress."

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