On paper, Novak Djokovic has proven to be the best men's tennis player of all time.
The 36-year-old Serbian has a record-breaking 23 Grand Slams under his belt along with 95 singles titles.
He has been ranked world No. 1 for a record total of 389 weeks in 12 different years. He is also the only man to achieve a triple Career Grand Slam in singles by winning each of the four majors at least three times
Now Djokovic returns to New York, seeking his fourth U.S. Open singles title. But what still motivates the highly achieved father of two?
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The answer is simple: Matches against players like world No. 1 Carlos Alcaraz -- the rising star who has taken the tennis world by storm.
The two tournament favorites have a head-to-head record of 2-2 with Djokovic winning the last match up -- a grueling three-setter -- a week ago in Cincinnati.
"Those are kind of the moments in matches that I still push myself on a daily basis for day in and day out, practice, sacrifice, commitment," Djokovic said at U.S. Open media day on Friday. "At 36, still have the drive."
Alcaraz won the showdown before between the two stars in the final of 2023 Wimbledon.
"I love competition," the tennis legend added. "I think the more you find yourself in those particular circumstances where you're experiencing adversity on the court, where things are not maybe moving the right way for you in terms of the performance of that day, in terms of tennis, or mentally you're not feeling your best, that's normally the best possible opportunity for you to grow mentally from that, to learn something. Normally in the face of adversity is where you learn the most.
"So that's kind of my mentality in these kind of matches, really trying to not accept defeat as an option, and really give it all, really give it all."
Djokovic returns to the U.S. Open after missing the event last year due to Centers for Disease Control and Prevention (CDC) Regulations as he is unvaccinated against COVID-19.
The Serbian has not won a U.S. Open singles title since 2018. He has won the three other Majors in the past year.
"I don't know how many more slams I'll have. I'll still keep going," Djokovic admitted. I don't have an end in my mind at the moment. I also understand that things are different when you're 36, so I have to be more appreciative, a bit more I guess present, treating every Grand Slam as maybe your last one in terms of commitment and performance."
Djokovic makes his 2023 U.S. Open debut on Monday against Alexandre Muller. They follow Coco Gauff-Laura Siegemund slated for 7 p.m. ET on Arthur Ashe Stadium.