Juan Carlos Ferrero, the former coach of Carlos Alcaraz, faced significant backlash from Alcaraz's fans after he posted a tribute to Jannik Sinner's recent victory at the Madrid Open on Alcaraz's birthday, May 5. Fans took to social media to express their discontent, labeling Ferrero's actions as 'salty' and inappropriate for someone who coached Alcaraz to seven Grand Slam titles. Alcaraz, who is currently ranked World No. 2 in men's singles tennis, celebrated his 23rd birthday while dealing with a wrist injury that will prevent him from participating in the upcoming French Open. The split between Alcaraz and Ferrero at the end of the 2025 season raised questions, especially given their successful partnership. Ferrero later explained that contract disagreements led to their separation, emphasizing that both parties had differing priorities. Currently, Ferrero is working as a mental performance coach for golfer Angel Ayora, while Alcaraz is now coached by Samuel Lopez.