The second set saw Fruhvirtova dominate her opponent, a former Grand Slam singles semi-finalist. After a marathon opening set lasting 77 minutes, the teenager clinched it 6-2 in quick time.
The Serbian 24-times Grand Slam champion trailed Korda 5-2 in the second set but broke the American as he served at 5-3 and his precise and powerful serving carried him to the finish.
The women's Grand Slams were all won by different players for a fifth straight year in 2021
World number one Carlos Alcaraz faces a potential quarter-final clash with old foe Jannik Sinner in his US Open title defence, and American Coco Gauff is on a collision course with defending champion Iga Swiatek on the women's side.
Iga Swiatek has been not been at her world-beating best in the months leading up to the U.S. Open but the Pole has both the talent and mentality to lift her game for the final Grand Slam of the year, tennis great Chris Evert said.
Andy Murray recovered from a slow start to beat Argentine qualifier Juan Ignacio Londero
The restart has divided opinion among the players, with some 200,000 new COVID-19 cases being reported globally every day and international travel restrictions still in place.
Sania Mirza and Rohan Bopanna outclassed Desirae Krawczyk and Neal Skupski to enter the mixed doubles final at the 2023 Australian Open.
Madison Keys was dumped out of the Miami Open third round on Sunday, falling 6-4, 6-2 to Philippine wild card Alexandra Eala
Making a comeback after a two-year hiatus, she enters women's doubles quarter-finals of Hobart International.
Indian tennis ace Sania Mirza and her Swiss partner Martina Hingis lifted their ninth title together this year beating the Spanish pair of Garbine Muguruza and Carla Suarez Navarro to clinch the WTA Finals women's doubles trophy, in Singapore, on Sunday.
American tennis ace Serena Williams has maintained her No 1 spot, while German Angelique Kerber has slipped to the third in the latest women's tennis world rankings issued by the WTA.
The World No 1 becomes earliest qualifier for WTA Finals
A summary of sports events and persons who made news on Saturday
Britain's Johanna Konta will become the first British woman to reach the top 10 of the WTA rankings for 32 years on Monday after reaching the China Open final on Saturday.
Wimbledon organisers have 'zero appetite' to turn the Championships into a 15-day event
Simona Halep announced her retirement from professional tennis on Tuesday after losing in the first round at her home event in Cluj.
Tennis great Serena Williams is recovering from surgery to remove a large cyst on her neck.
The 27-year-old Romanian beat Sloane Stephens at Roland Garros to win her maiden Grand Slam title in June and will have spent 40 weeks at the top of the rankings by the end of the season.
The Dutchman collapsed on the court after converting his sixth match-point to end an absorbing three hour, seven minute affair under sunny skies on Stadium One court.
* Swiatek started playing tennis in an attempt to emulate her older sister, who competed briefly on the junior circuit.
The first set was over in 31 minutes with the No. 4 seed making the most of a weak Raina serve while saving two break points on her own serve.
"Unfortunately I am no longer able to train and play the way I used to, and recently my body can't live up to my expectations," Radwanska, 29, said in a post on Facebook.
The duo of Sania Mirza and Martina Hingis sailed into the 10th final of the year at the Women's Tennis Association's (WTA) Finals after beating Chinese Taipei's Chan Hao-Ching and Chan Yung-Jan in straight sets, in Singapore, on Saturday.
Djokovic saved three breakpoints in stifling conditions to go 5-4 up but lost the opening set in a tough tiebreak as Opelka cranked up his serve
Opelka edges Kyrgios to set up all-American final with John Isner in Houston
India's tennis star Sania Mirza retained her numero uno status in women's doubles for the second consecutive year, despite failing to defend the WTA Finals Singapore title with partner Martina Hingis. Defending champions Sania and Hingis had lost to Ekaterina Makarova and Elena Vesnina in the semi-finals of the WTA Finals Singapore on Saturday.
Following Sania Mirza's quarter-final appearance in the Family Circle Cup last week, the Indian tennis ace jumped 17 places to 73rd position in the latest WTA singles rankings issued on Monday.
Tatiana Golovin stunned top seed Nadia Petrova 6-1, 6-2 in the final of the Amelia Island championships.
Novak Djokovic equalled Roger Federer's all-time record for most weeks as ATP world number one
American teenage sensation Coco Gauff became the youngest player to win a WTA title in 15 years as she beat former French Open champion Jelena Ostapenko in the Linz Open final on Sunday.
It proved a happy Halloween for Czech Petra Kvitova after she made the most of coming back from the dead to set up a title-match showdown with Agnieszka Radwanksa at the WTA Finals.
Naomi Osaka has parted ways with coach Wim Fissette after four years together across two stints, the 26-year-old announced late on Friday.
Svetlana Kuznetsova had been steamrolled in the second set and was a break down in the decider of her WTA Finals opener against defending champion Agnieszka Radwanska on Monday. So what did the Russian do to turn the match around?
Top seed Carlos Alcaraz snapped Daniil Medvedev's 19-match win streak with a 6-3, 6-2 rout in the Indian Wells final on Sunday.
Petra Kvitova overcame a sluggish start and 10 double faults to beat Madison Keys 6-7(6), 6-4, 6-3 on Saturday and advance to the final of the Cincinnati Open, where she will face Caroline Garcia, the first qualifier to reach the final of a WTA 1000 tournament.
The hard court, outdoor competition in Lexington, Kentucky, marked the WTA's first tournament in the United States since the coronavirus outbreak forced almost all sport into a long break earlier this year.
Four-times Grand Slam winner Naomi Osaka fired off 18 aces as the Japanese former world number beat Swiss Belinda Bencic 4-6, 6-3, 6-4 on Thursday to reach her first Miami Open final.
Naomi Osaka has witnessed a huge change in her career after claiming a maiden Grand Slam title in 2018, but the rising star of women's tennis will not be changing her quirky personality in media appearances that has endeared her to so many.
Linette will battle against Canada's Rebecca Marino, the seventh-seed, in the last eight on Friday.
