Cape Town - Proteas skipper AB de Villiers has admitted that he fears being punished for his side maintaining a slow over-rate in one-day cricket.De Villiers was banned for South Africa's last two ODIs against New Zealand earlier this year after his team failed to complete their overs in the time allowed. The players were also fined 100 percent of their match fees for the game in Paarl in January.The skipper said they really tried to up the tempo against Pakistan on Sunday, yet were still an over behind the allotted time."I hate the word over-rate," De Villiers said on the Beeld website."I gave my best, we worked hard on it (to stay with the tempo) and halfway through our overs we were still behind."It's worrying because in the last 15 overs, when the ball gets hit out the park and you have to think about field placings, time gets lost."We were slightly behind - it's tough to determine exactly what the problem is."We're still working on the problem. At least it was much better (against Pakistan) than in Paarl - where we were six overs behind."I felt in control. Everybody played their part. There were quick exchanges between overs yet we were still behind. We do not have four spinners in our team like Pakistan," said De Villiers.A similar transgression in the next 11 months could land De Villiers in more serious trouble though. He and his team will be eager to further work on the problem when they gather in Centurion on Wednesday ahead of the second ODI there on Friday.South Africa won the first ODI in the five-match series by 125 runs in Bloemfontein last Sunday.