Petra Marčinko

Petra Marčinko (born 4 December 2005) is a Croatian tennis player.

Marčinko has a career-high WTA singles ranking of 132, achieved on 23 October 2023. She has won six titles in singles and two in doubles on the ITF Women's Circuit.

Marčinko had won nine singles and seven doubles titles on the ITF Junior Circuit. She achieved the number-one junior ranking on 13 December 2021.

In December 2021, she completed a remarkable late-season surge as singles and doubles victories at the prestigious Orange Bowl championships saw her climb nine places to finish as the year-end junior world No. 1. At the beginning of 2022, she won her first junior Grand Slam title at the Australian Open, defeating Sofia Costoulas in the final in straight sets.

Marčinko made her WTA Tour debut at the 2022 Morocco Open in Rabat extending her season win-loss record to 20-4, after receiving a wildcard and recording an upset over Rebecca Peterson for her first top 100 win.

Marčinko won her sixth consecutive ITF Women's Circuit title at the 2023 Caldas da Rainha Ladies Open, defeating Léolia Jeanjean in the final in straight sets, and set the new Croatian record for the youngest women's player to win six professional singles titles before turning 18.