Novak Djokovic turns 37 next year but the Serbian says his appetite for success will only increase with young challengers awakening the "beast" in him.
The world No. 1 enjoyed an extraordinary 2023 by winning three out of the four Grand Slams to take his tally to 24, two more than his great rival Rafael Nadal and four more than the retired Roger Federer.
Djokovic did not have it all his own way, however, with 20-year-old Carlos Alcaraz denying him a fifth-straight Wimbledon crown in a thrilling final and 22-year-old Jannik Sinner dashing his hopes of Davis Cup glory.
"The young guys who are very hungry and very inspired to play their best tennis against me is an additional motivation," Djokovic said on CBS News programme "60 Minutes".
"I think they kind of awaken a beast in me."
Djokovic beat Alcaraz in three of their four meetings this year - including the French Open semifinals where the Spaniard suffered full-body cramps - but the Serb said his young rival had become a real threat.
"He's as a complete of a player as I have seen in ages," Djokovic said, adding that he used his defeat in the Wimbledon final as motivation for the US hardcourt swing, where he won at Cincinnati and Flushing Meadows.
"It's a great opportunity for me to reinvent myself and really push harder than I ever did."