As a golden tennis era transitions into its next guise, when, how, and why to retire is one of the biggest questions in the sport.

Roger Federer ’s former coach has shared his surprise at Rafael Nadal ’s retirement announcement. The Spaniard recently confirmed that he will end his wildly successful career at next month’s Davis Cup Finals in Malaga. While Ivan Ljubicic was shocked by his decision, Federer’s old mentor shared his wish to see Nadal get a fitting send-off.

In a recent interview with DAZN Sport, the 22-time major champion was asked to push the conversation further and compare the rivalries between him, Federer and Djokovic to the new rivalries being made between young players in tennis—like the battles between Carlos Alcaraz of Spain and Jannik Sinner of Italy.