Jelena is a Serbian professional tennis player and a long-time member of the Serbian national team. She is the owner of the crown of the most successful tennis player in the national team, she was awarded the Order of the Star of Karađorđe. Eight times she was the best Serbian tennis player in a season.

Ranked first on the World WTA list in 2008, tennis player with over 600 victories. She is one of the most consistent players ever, as she was in the top 10 on the WTA list continuously for more than four years. She is one of only three tennis players who were number 1 in both junior and senior competition, as well as one of seven who beat both Williams sisters, Venus and Serena in the same tournament…

She played 60 consecutive Grand Slams. On one of them, during the collaboration with prof. Dr Zoran Pajić, at the 2017 Australian Open in the third round of the main tournament, she played a match against Svetlana Kuznetsova, which will be remembered as the longest match of the year and the 3rd longest in the history of the Australian Open, which lasted 3 hours and 46 minutes. For such a turn of events, excellent physical preparation was necessary!