South African batsman David Miller on Friday backed his captain AB de Villiers, who is in poor form in the ongoing Champions Trophy cricket tournament, and said it was very human-like for the skipper to fail.The 33-year-old star batsman has been in the roughest patch of his career failing to click in either of the two matches played against Pakistan and Sri Lanka scoring zero and four runs respectively."It is tough (when AB doesn't perform). He is the best player in the world so it's nice when he does perform, and that's 95% of the time. I haven't seen him go out for a nought too many times in his career. He is human at the end of the day and there are enough good batters in the team to contribute as well. I don't think it's a huge problem at all," the 27-year-old batsman was quoted as saying by Fox Sports. "We've done well over the last two-and-a-half years and all the batters that we have can do the job. AB, unfortunately, didn't come off but he is definitely due on Sunday."South African coach Russell Domingo has also put his weight behind de Villiers ahead of the virtual quarter-finals against India on Sunday."I have no concerns about AB de Villiers. "I'm expecting him to put in a big performance on Sunday. He's that type of player that when the team needs him, he'll turn it up on Sunday. I'm sure about that," he said.