Markos Kalovelonis

Markos Kalovelonis (, Марк Георгиевич Каловелонис; born 18 May 1994) is a Greek-Russian tennis player.

Kalovelonis has a career high ATP singles ranking of World No. 445 achieved on 13 June 2016. He also has a career high ATP doubles ranking of World No. 178 achieved on 8 August 2023. Kalovelonis has won 21 ITF doubles titles.

Kalovelonis has represented Greece at the Davis Cup where he has a W/L record of 6–5. He also represented Greece in the ATP Cup in 2020, 2021 and 2022.

Kalovelonis is the son of former Greek tennis player, George Kalovelonis and Russian Karina Nazarenko. In 2014, Kalovelonis decided to represent Russia instead of Greece. In 2019, Kalovelonis switched back to represent Greece. He is fluent in Russian, Greek and English.