LONDON (Agencies) - South Africa bowling coach Allan Donald said they are planning to topple England from the top of the ranking charts when the Proteas tour the country for a Test series next year. Donald, who was Englands bowling coach at one time, is now a part of the South Africas support staff headed by his former Test teammate Gary Kirsten. Having got to number one in the world, Englands next challenge is to stay there, but it also means that they are there to be toppled. For other sides it means that when you get a sniff of beating England you have to grasp it, the former fast bowler said. It is going to be a huge one for us. We always weigh ourselves against England and Australia and next years series is going to have more on it with England going number one in the rankings. Neither side will hold back or take a backwards step so it promises to be a fantastic series. England at home will have lots to prove and we have a fantastic record in England, he added. During his stint with England, Donald had worked closely with the current coach Andy Flower, who was then the teams batting coach, and he credits the Zimbabwean for the teams journey to the top. I have a serious amount of respect for Andy Flower. He has brought hardness and a real mental toughness to the team. Hes proud of his players and he instills such belief in his team. Under him England have won the World Twenty20, retained the Ashes and now got to number one in the world. He has made them a difficult team to beat. One of the main reasons for Englands success is that they have such a well-balanced attack. Broad, Anderson, Bresnan and Tremlett these guys are making a serious impact, said Donald