Novak Djokovic has suffered a terrible loss of form since the start of 2016, when the most recent of his 12 Grand Slams arrived.
Djokovic aims to rediscover his old magic this week at the Monte Carlo Masters, live on Sky Sports - watch the video at the top of this page which tells the story of his slump.
Boris Becker and Andre Agassi have come and gone as Djokovic's coaches, as his form continued to decline. A long-term injury absence didn't help matters.
This year he has been beaten by Hyeon Chung at the Australian Open then world No 109 Taro Daniel at Indian Wells.
Will Djokovic recover his old excellence in Monte Carlo?
Coverage of the ATP Monte Carlo Rolex Masters gets underway from 10am on Sky Sports Arena every day this week.
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