Novak Djokovic teared up while paying tribute to the late Nikola Pilic, who the Serb considers his 'tennis father.' The tribute came in the aftermath of the former No. 1's winning return to action at the ongoing Hellenic Championship in Athens, Greece. The 24-time Major champion also briefly showed off his language skills as he spoke a few words of Greek to delight the home crowd.Pilic, a Croatian former tennis star who represented SFR Yugoslavia, played an instrumental role in Djokovic's early development. The Serb honed his skills under the Croat's tutelage in an academy the latter ran near Munich, Germany. Sadly, Pilic passed away at the age of 86 in September this year, leaving a lasting void in the Serb's life.Following Novak Djokovic's 7-6(3), 6-1 win over Alejandro Tabilo in the second round of the Hellenic Championship, the Serb featured prominently in the on-court tribute to the late Nikola Pilic. Here, as a video commemorating Pilic was played on the courtside screens, the World No. 5, clearly moved by the tribute, tore up. Watch the emotional moment below:On a lighter note, the 100-time ATP Tour-level singles titlist, having moved to Athens with his family, spoke a bit of Greek during his post-match, on-court interview. Watch this particular moment below:"A feeling of emptiness and sadness has taken over me" - Novak Djokovic after tennis father's passingNovak Djokovic during a press conference at the 2025 Madrid Open (Source: Getty)Not long after the news of Nikola Pilic's death broke in September, the late Croat's former pupil Novak Djokovic put out an emotional statement via social media. Expressing gratitude towards Pilic and his wife, the Serb wrote on Instagram:"I received some sad news today while I was in the field finishing my training. A feeling of emptiness and sadness has taken over me. I hope you felt how much you meant to me in your career and life. Your influence on my development as a man and tennis player remains indelible. I am eternally grateful to you and your lovely wife Mia for accepting me as your own son when I was 12." (translated from Serbian)The former No. 1, the top seed in Athens, is slated to face sixth seed Nuno Borges next in the quarterfinals of the ATP 250 event. Amid his campaign in the Greek capital, there are lingering question marks over the Serb's ATP Finals participation, with the 38-year-old having stated that he will decide if he will play in Turin or not after his Athens run comes to an end.