Kasatkina, coached by Vladimir Platenik from Slovakia, has won one singles and one doubles WTA title on in her career. She also won the girls' singles tournament at the French Open in June 2014, defeating Ivana Jorović in three sets in the final. Kasatkina was part of the Russia team that won the Junior Fed Cup in 2013.
Daria was born 7 May 1997 in Tolyatti, Samara Oblast. Her father Sergey works at the Volga Automobile Plant, and her mother Tatyana is a house wife. Tatyana and Sergey are both Candidates for Master of Sports—Tatyana in athletics and Sergey in ice hockey. Her brother Aleksandr brought her to tennis.
Kasatkina took the racket at age six, she was 11 when she was coached by Maxim Prasolov. Three years later her new coach became Damir Rishatovich Nurgaliev, a well-known tennis coach in the Samara Oblast. The fourteen year old won her first tournament at the fourth-graded Samara Cup. A year later she debuted at Grand Slam junior tournaments. The Russian team of Kasatkina, Veronika Kudermetova and Aleksandra Pospelova won the Junior Fed Cup in 2013 defeating Australia in final in San Luis Potosí, Mexico.
She started her professional career in 2013. Within a year, from year-end 2014 to 2015, Kasatkina jumped 300 ranking positions.
In 2014, she won a junior Grand Slam title at the French Open by defeating Ivana Jorović in the final.
Kasatkina made her senior Grand Slam debut at the US Open in the main draw as a lucky loser in 2015, after Maria Sharapova withdrew due to injury. She beat Daria Gavrilova and Ana Konjuh to make the third round, losing to Kristina Mladenovic. She won her first career doubles title at the 2015 Kremlin Cup with Elena Vesnina. She also reached semifinals in singles as a qualifier, defeating Carla Suárez Navarro in the quarterfinals before falling to Anastasia Pavlyuchenkova.
At the 2016 ASB Classic, Kasatkina scored the biggest victory of her career, defeating defending champion, seven-time Grand Slam champion and former world number one Venus Williams in the first round in three sets. But in the second round she lost to Japanase Nao Hibino in tight three sets. At the Australian Open she was drawn against 27th seed Anna Karolína Schmiedlová in the first round and won in straight sets. She then won in straight sets over Konjuh in the second round, but lost to world no. 1 Serena Williams in the third round in 44 minutes.
Kasatkina debuted at the 2016 Fed Cup against the Netherlands in the first round, winning the dead rubber in doubles with Ekaterina Makarova. Then, in St. Petersburg, she had the best results among the Russian participants, reaching the semifinals in singles, falling to Belinda Bencic.
At the 2016 Qatar Total Open, Kasatkina and doubles partner Elena Vesnina rematched No. 1 duo Hingis/Mirza, whom they previously lost to in St. Petersburg. The Russian duo also broke the best-ranked duo's winning-streak record of 41 winning matches in a row.
Following this, Kasatkina debuted at the 2016 BNP Paribas Open where she reached her first Premier Mandatory quarterfinal with wins over Daniela Hantuchová, Anna-Lena Friedsam, Monica Puig and twelfth seed Timea Bacsinszky before falling to eighteenth seed Karolína Plíšková in straight sets. Kasatkina also paired up with compatriot Elena Vesnina in the doubles but the pair lost in the second round to eventual finalists Karolína Plíšková and Julia Görges in three sets. Following this tournament, Kasatkina reached a career high in singles and doubles.
The next tournament Kasatkina entered for was the 2016 Miami Open where she defeated Kateryna Bondarenko in the first round. In the second round she lost to Simona Halep. Kasatkina's rankings in singles and doubles again reached a new career high.
In Charleston, Kasatkina won her 100th match in WTA and ITF combined, by defeating the Chinese Zheng Saisai in straight sets. She reached the quarterfinals, where she was defeated by eventual champion Sloane Stephens.
At the 2016 French Open, Kasatkina won her first two matches in three sets. She beat Anna-Lena Friedsam and Virginie Razzano in the first two rounds. In the third round, she lost to Kiki Bertens in a hard fought three set match, 2–6, 6–3, 8–10.
Kasatkina again reached the 3rd round of a Grand Slam at Wimbledon, where she lost 5-7 6-4 8-10. Shortly before the matchball for Williams it began to shower.
Kasatkina reached her second Premier quarterfinal at the Rogers Cup, losing there to Angelique Kerber. On the way she beat 13th-seeded Samantha Stosur and 7th-seeded Roberta Vinci. She has qualified for the Olympic Games in singles, and in doubles she replaced injured Margarita Gasparyan to team up with Kuznetsova. In her first Olympics, she has beaten youngster Ons Jabeur of Tunisia in three sets. In the second record she easily beat Saisai Zheng and recorded her third win in Rio with a two setter against Sara Errani. She lost against seventh seed Madison Keys in the quarterfinal. In the doubles she paired with Svetlana Kuznetsova. The duo has lost in the quarterfinal to the Czech pair Andrea Hlavackova and Lucie Hradecka.
Kasatkina started the new season in Brisbane, reaching the second round before being defeated by Garbiñe Muguruza. She reached the quarterfinals of the Sydney International, defeating world number one, Angelique Kerber, for the first time. In doubles, she tried a partnership with Irina-Camelia Begu in Brisbane but since Sydney, she continued partnering with Daria Gavrilova. Later on, she defeated Kerber for the second time during the second round of the Qatar Open before losing the quarterfinal to Monica Puig. She won the Volvo Car Open in Charleston, South Carolina by defeating Kovinic, Puig, Gavrilova, Begu, Siegemund, and Ostapenko. This was her first career WTA singles final and first deep run in a Premier event.
Kasatkina prefers watching men's over women's tennis, with her favourite tennis player being Rafael Nadal. She also enjoys watching football, and is a fan of FC Barcelona.Russian Cup: 2014 Junior of the Year
WTA Breakthrough of the Month – April 2017, thrice nominated for January, February and March 2016.