IF AB de Villiers glanced last week into his rear view mirror to check on the progress of his rivals for the title of the best batsman in the world he might have had a shock. Kumar Sangakara, of course, remains just ahead of him but, hurrying up quickly, he would have seen two young pretenders who were nowhere near him 12 months ago. Earlier in his career De Villiers was a prolific scorer of big centuries but more recently he appeared to have been caught between the different batting styles required by the three distinctive types of cricket that he plays. The measured pace of his Test match batting seems to have been infected by the frenetic requirements of the shorter versions of cricket. It is almost as though AB was no longer prepared to accumulate the big scores but was tempted by his mastery of all bowling to throw restraint to the winds of fortune.