Novak Djokovic has contested 31 Grand Slam finals and faced just about every scenario possible in collecting 20 titles, but even he will not know what to expect in Sunday's Wimbledon showdown against Australian showman Nick Kyrgios.
The 35-year-old Serbian, bidding for a fourth successive title, will prepare for every eventuality, but the likelihood is that world No. 40 Kyrgios will still conjure up some surprises.
It could be an underarm serve played between the legs on the first point of the match, a tweener drop shot from the baseline on a break point or picking a fight with a fan.