South Africa’s shock Test series defeat against Sri Lanka came as a major jolt to a team which had become accustomed to dominating Test matches at home. The unheralded Sri Lankans exposed flaws in both South Africa’s top-order batting and their much-vaunted fast bowling attack in winning both Tests in a two-match series. Coach Ottis Gibson was asked after the second Test in Port Elizabeth whether South Africa’s policy of playing on pace-friendly pitches had affected the form and confidence of the home team’s batsmen, who struggled to totals of 235, 259, 222 and 128 against Sri Lanka. “No,” he said. “We’ve got runs on these pitches before. We just haven’t batted well enough in this series.” The reality, though, is that batting struggles have become a trend, with none of the current top six batsmen averaging above 40 since the start of 2018. Successive series wins against India, Australia and Pakistan were achieved when moderate totals proved enough because of South Africa’s bowling firepower. Some changes seem inevitable. Gibson’s contract expires after the Cricket World Cup in July and he has refused to comment on the likelihood of staying in the job. The Sri Lanka series has also put…