Maria Sakkari will make her debut at the Akron WTA Finals in Guadalajara. The Greek qualified for the prestigious year-ending championships after advancing past an ill Anna Kalinskaya, 6-2, 1-0, ret. in the second round of the VTB Kremlin Cup on Thursday.

Read more: Maria Sakkari earns historic qualification for 2021 Akron WTA Finals Guadalajara

"It was a very important match," Sakkari said during her post-match press conference. "I knew that before I stepped on the court, because I knew that if I won that match, I would qualify [for the WTA Finals]. It’s achieving one of my biggest goals this year, it’s very satisfying.

"I’m very proud of myself and my team that we actually made it to the Finals for the first time, and for the first time in the history of Greece for a female tennis player.

"I was very hard on myself up until this year....Growing, and also getting older and more mature, you see certain things different. Being nice to myself was one of the most important things I’ve changed this year, being nice during the games and the matches."

Sakkari's surge: Sakkari continues a breakthrough season where she became the first Greek woman to ascend into the Top 10, reached her first WTA singles final since 2019 in Ostrava, and made two Grand Slam semifinals at Roland Garros and the US Open.

Sakkari, currently at her career-high ranking of World No.7, has made the elite eight in Moscow in her second appearance at the tournament, following a first-round loss to former champion Anastasia Pavlyuchenkova in 2019.

Superb set: No.3 seed Sakkari eased through the first set in half an hour, going 9-for-9 behind her first serve, and never facing a break point. After Sakkari grabbed an early service break in the second set to extend her commanding lead, an ailing Kalinskaya retired due to viral illness.

Kalinskaya has recently experienced strong success in a compressed timeframe, having won eight of her last nine matches in the past three weeks before her clash with Sakkari. She made a sterling run to the Indian Wells round of 16 as a qualifier just last week, before qualifying again for the Kremlin Cup main draw.

Kontaveit bests Petkovic, rolls into Moscow QF: Highlights

Kontaveit cruises past Petkovic

Earlier on Thursday, No.9 seed Anett Kontaveit of Estonia made her way into the VTB Kremlin Cup quarterfinals, easing past former Top 10 player Andrea Petkovic of Germany, 6-1, 6-4.

"I thought I played a decent match," Kontaveit told the press, after her win. "I was very consistent in the first set, and then it got a little bit more competitive.

"I think she raised her level in the end of the first and in the second set as well, so it got a little bit close. But I felt like I was trying to stay tough, and I managed to do that pretty well today."

World No.20 Kontaveit is into the Moscow quarterfinals for the second time in her last two showings. She also reached the elite eight in her most recent appearance in 2018, before falling to eventual finalist Ons Jabeur.

VTB Kremlin Cup

It took the Estonian only an hour and nine minutes to best Petkovic and improve her head-to-head against the German to 2-0. Kontaveit slammed five aces, won 77 percent of her first-service points, and converted four of her seven break points on the day.

Kontaveit continues a blistering second half of the season, having won 18 of her last 20 matches. That run of excellent form includes her second and third WTA singles titles, at Cleveland and Ostrava respectively. 

Awaiting Kontaveit in the quarterfinals is No.2 seed Garbiñe Muguruza of Spain. World No.5 Muguruza has won two of their three previous meetings.