Actually I always wanted to share about the above topic but each time I tend to forget about it. While having lunch with my colleagues the other day, they asked me why I always chose the same type of food: sambal petai and udang, kari ayam and a telur goreng. For the past two months, we went to the same restaurant (although not everyday) and I've been taking the same menu without realizing that!
And the other day while listening songs from my laptop, my sister complained because I've been listening to John Legend's songs over and over again without realizing it. These are just two examples.
Now, guess which sports player who's even worse than me? Yes, you are right! Nadal has some of the most obsessive compulsive habits. He pulls his underpants almost before every pre-serve, straighten his socks, make sure his water bottles are placed back exactly on the same spot and bites his winning trophies.
Based on some of the discussion in tennis forum, it seems that those are Nadal's rituals probably inducted by his coaches as a way to focus himself in the game and control his explosive energy and emotional behaviour while playing in competition.