Nick Kyrgios firmly disagrees with Serena Williams' ex-coach, who claims Alcaraz & Sinner are better than peak Federer, Nadal & Djokovic

Nick Kyrgios stuck with Novak Djokovic, Roger Federer and Rafael Nadal - the Big 3 of tennis in their prime in comparison with current sensations Jannik Sinner and Carlos Alcaraz.