HEATHER WATSON

Novak Djokovic found himself locked in a tight fourth-round match at Wimbledon against a wild-card entry making his Grand Slam tournament debut.

Third-seeded Ons Jabeur saved five set points in the first-set tiebreaker before beating Elise Mertens 7-6 (9), 6-4 to reach her second straight Wimbledon quarterfinal.

Tatjana Maria's Wimbledon run appeared to be in trouble when Maria Sakkari was a point away from going up 5-1 in the second set of their third-round match. Then Maria turned it around — in a hurry. The 34-year-old German won the next three points to get to 4-2 and later rattled off five games in a row to beat the fifth-seeded Sakkari 6-3, 7-5 at the All England Club.

Three-time defending champion Novak Djokovic's next opponent is an oft-injured guy ranked outside the top 100 and making his Grand Slam debut thanks to a wild card.

Jannik Sinner withstood the aces and reached the fourth round at Wimbledon by beating John Isner 6-4, 7-6 (4), 6-3.

"If you're broken after a three-hour match the day before, you can't play professional," Tamara Korpatsch wrote on Instagram. "That's my opinion."

Daniil Medvedev never gave Andy Murray a chance.

Shelby Rogers beat Anhelina Kalinina 7-6 (2), 6-2 and Sloane Stephens outlasted Heather Watson 6-7 (5), 7-5, 6-1 in opening matches at the BNP Paribas Open.

Top-ranked Ash Barty has reached the semifinals of the Western & Southern Open with a 6-2, 6-4 victory over Barbora Krejcikova.

When Tennys Sandgren resumed practicing after his can’t-go-anywhere hard quarantine ended, the American said Tuesday, his hands developed blisters from holding a racket. And, like Azarenka, both Sandgren and Pospisil lost their opening matches. “I wouldn’t say the whole tournament is a joke, but for some players, it’s not feasible. “I needed fresh air or maybe a bigger room or better conditions to play against the best players,” she said. Players in the “regular” quarantine were allowed to leave their rooms for five hours per day during the first two weeks after getting to Australia.

Italian tennis player Simone Bolelli, left, and Argentina's Maximo Gonzalez are escorted to their training session in Melbourne, Australia, Monday, Jan. 18, 2021. The number of players in hard quarantine swelled to 72 ahead of the Australian Open after a fifth positive coronavirus test was returned from the charter flights bringing players, coaches, officials and media to Melbourne for the season-opening tennis major. Some players have expressed anger at being classified as close contacts merely for being on board those flights with people who later tested positive. But local government, tennis and health authorities have said all players were warned of the risks in advance. The Australian Open starts Feb. 8 following a week of warmup tournaments at Melbourne Park and the ATP Cup.

Health authorities confirmed there'd been three positive tests for COVID-19 returned on Saturday, and another on Sunday. The Australian Open starts on Feb. 8. Kei Nishikori, the 2014 U.S. Open runner-up, and two-time Australian Open champion Victoria Azarenka were among a group of players who arrived on the flight from Los Angeles. Also, Americans Madison Keys and Tennys Sandgren returned positive tests, but Sandgren was given permission to fly after Australian health authorities determined he was no longer contagious though still shedding viral particles. South Australia health officials “confirmed that there is no one who has an active COVID-19 infection in the entire tennis cohort based in Adelaide,” the Australian Open said on Twitter.

Singer JoJo Siwa has responded to complaints about a board game for kids that is branded with her name and image. Siwa, who is popular for her Nickelodeon shows and YouTube channel for kids, took to Instagram Monday to address concerns some had with the game "JoJo's Juice." Her TikTok video, which was posted on Saturday, went viral with more than 600,000 views on the app. In a video posted to Instagram and TikTok Monday, Siwa said, "Now, when companies make these games, they don't run every aspect by me. "Now when I first saw this I was really, really, really upset about how gross these questions were and so I brought it to Nickelodeon's attention immediately.