Aryna Siarhiejeŭna Sabalenka (born 5 May 1998) is a Belarusian professional tennis player. She is the current world No. 1 in singles and a former world No. 1 in doubles. Sabalenka has won three major singles titles and two major doubles titles, the latter both partnering Elise Mertens. She has won another 15 singles titles and four doubles titles on the WTA Tour.
Sabalenka came to prominence in 2017 when, together with Aliaksandra Sasnovich, they led the Belarus Fed Cup team to a runner-up finish despite both of them being ranked outside the top 75 at the time. She finished 2018 and 2019 ranked No. 11 in the world in singles. Following two major singles semifinal appearances in 2021, Sabalenka peaked at the world No. 2 ranking but struggled to maintain that success in 2022 consistently. In 2023, she won her first major singles title at the Australian Open and obtained the world No. 1 ranking, being named the ITF World Champion for the season. She defended her Australian Open title and won the US Open the following year, clinching the year-end No. 1 ranking.
Sabalenka also began playing doubles regularly in 2019. With Mertens as her partner, she found instant success by winning the Sunshine Double (Indian Wells and Miami) that same year. After the US Open doubles title later in the season, she qualified for the WTA Finals for the first time. With the 2021 Australian Open doubles title, Sabalenka became the world No. 1 in the discipline, after which she shifted to playing primarily singles.

Sabalenka has a very aggressive style of play, often accumulating high numbers of winners and unforced errors. With her height, she also has a very powerful serve.