Novak Djokovic’s eternal struggle to rediscover his form could be down to his marital problems off the court, John McEnroe has claimed.

The pundit even compared the Serb’s downfall to that of golf star Tiger Woods who has never rediscovered his top form since it was revealed he had been cheating on his wife back in 2009.

Djokovic admitted last year after a tough summer, in which he was dumped out of Wimbledon and the Olympics, that problems off the field with his wife Jelena had been a distraction.

Jelena has since returned to his side, appearing in his box at tournaments, but Djokovic has yet to rediscover the form that saw him dominate the sport.

And the 58-year-old believes the Serb’s ‘off-court issues with the family’ could hinder his attempts to get back to his previous best.

Speaking to the camera during the second day’s coverage at Wimbledon, the American said on Djokovic’s previous problems: ‘That’s going to throw you. If you’re distracted, you’re not the same player.

‘The person that comes to mind immediately with Novak is golfer Tiger Woods.

‘He had the issues with his wife, he seemed to go completely off the rails and has never been even close to the same player.

‘So we’re starting to say, ‘Wait a minute, is this possible with him?’

‘This isn’t a physical thing, this is a mental thing. There are definitely some issues.’

The Serbian is through to the second round at the All England Tennis club after his first-round opponent Martin Klizan retired injured on Tuesday.

Djokovic will face Adam Pavlasek of the Czech Republic in the second round.

By Harry Slavin for Mail