Novak Djokovic is in 'a league of his own,' says Sky Sports expert and former Germany Davis Cup captain Patrik Kuhnen, especially when it comes down to mentality.
Djokovic overcame both injury and two of the best younger players on the ATP Tour to claim a ninth Australian Open title this month.
It was his 18th major in total, and puts him in a great position to challenge the record (20) currently shared by Rafael Nadal and Roger Federer.
"There is much to suggest that the Serb will eventually overtake Federer and Nadal and become the champion of records," Kuhnen told Sky Sports Germany.
"The Australian Open once again made it clear to me: Djokovic is in his own league, especially mentally.
"The 'Djoker' gets even more in the heads of his opponents. Due to his ability to seal off the court, to return so brilliantly and to play flawlessly in the decisive moments, the pressure increases on the opponent to try something special.
"The top favourite for the French Open is, as always, Rafael Nadal. The top favourite for Wimbledon and the US Open must currently be Novak Djokovic."
Djokovic played both Alexander Zverev and Daniil Medvedev en-route to winning the Australian Open, and Kuhnen thinks it was a wake-up call for just how far they still are from the standard set by the big three.
"In addition to Dominic Thiem, I thought Daniil Medvedev would be able to change the guard at the Grand Slams," Kuhnen added.
"But men's tennis seems to be a little further away from a changing of the guard after this Australian Open. Novak Djokovic was too impressive, too dominant in the decisive moments.
"For the young challengers, it is still a very special attraction to conquer the big three. Against Djokovic, the hurdle seems to be particularly big, especially mentally."
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