John McEnroe has described Rafael Nadal as one of the most phenomenal athletes of all time and a freak individual, but is concerned the 35-year-old's body could be a worry in his Australian Open semi-final with Matteo Berrettini. Nadal has been in excellent form in what is his first Grand Slam since picking up an injury in last year’s French Open, but he was pushed to the limit by Denis Shapovalov in the quarter-finals. Ad/> Nadal required treatment for a stomach problem, and his camp revealed he lost a huge amount of weight during the gruelling five-set encounter.