Novak Djokovic tightened his iron grip on men's tennis in 2023 but fans got another glimpse of the sport's future flagbearers as Carlos Alcaraz stopped the Serb from sweeping the Grand Slams and Jannik Sinner landed a late blow.
Playing some of his best tennis at 36, and having crossed a record 400 weeks at the top of the world rankings, Djokovic is primed to push for a Golden Slam of winning all four majors and the Olympic crown in Paris next year.
"The drive is still there. My body has been serving me well, listening to me well," Djokovic said after clinching his record seventh ATP Finals title.
"The mindset is the same. I'll keep going."
Djokovic's supremacy in an extraordinary season helped him equal the injured Rafa Nadal's tally of 22 major titles at the Australian Open with a hamstring tear and surpass his old rival at the French Open, crushing a cramping Alcaraz along the way.
But a rejuvenated Alcaraz ended Djokovic's Wimbledon reign in an epic five-setter to capture his second Grand Slam title and suggest that, after nearly two decades of "Big Three" control, a changing of the guard was imminent.
Those hoping a new era was about to begin would be disappointed, however, as Djokovic lifted a 24th Grand Slam title at the US Open and secured the year-end number one spot at the ATP Finals where he dismantled Sinner to prevail.
Few would dare bet against the Serb enjoying another stellar season in 2024 but if anyone is going to stop him it will be the fearless and fast-learning Alcaraz.
The 20-year-old Spaniard will need to remain injury-free and iron out the flaws that derailed him in three of their four meetings in 2023 if he is to go toe-to-toe with Djokovic.
Sinner emerged as another potential threat deep into the season, stunning Djokovic twice in one day at the Davis Cup before masterminding Italy's triumph.
"Djokovic said he was ready to win the four Grand Slams and Olympic gold, but we're here to stop him," Alcaraz said during an exhibition event in Mexico last week, as he looked ahead to an "intense" 2024.
Nadal, a member of the all-conquering triumvirate alongside Djokovic and the retired Roger Federer, will look to add a final chapter to his glittering but injury-plagued career in what is likely to be his last season on tour.
The Spaniard has not played since suffering a hip problem at the Australian Open and it would be a huge surprise if he is able to make up ground on Djokovic in the Grand Slam chase.
The women's game was a refreshing contrast to the men's, churning out four different Grand Slam champions in Aryna Sabalenka, Iga Swiatek, Marketa Vondrousova and Coco Gauff, with the fight for the year-end top ranking going down to the wire.
French Open champion Swiatek returned to her perch to deny a vastly-improved Sabalenka at the end of a gruelling campaign but may find 2024 more challenging if Elena Rybakina rediscovers her best form and Ons Jabeur steps up her bid for a first slam.
Major champions Naomi Osaka and Angelique Kerber will also return after their maternity breaks, following in the footsteps of Caroline Wozniacki, with the trio adding spice to the ultra-competitive field.