Graeme Smith believes that South Africa's bowling attack will be important to helping his side tighten their grip on top spot in Test rankings.

The Proteas earned the number one status thanks to a 2-0 series victory over England, which they secured earlier today.

Looking ahead, captain Smith is hoping that his team can hold on to the summit for the foreseeable future.

"There are a lot of good teams around, England are one of them, but we need to have a good depth of players, such as fast bowlers, if we're going to be number one for any length of time," he told BBC Sport.

Smith will take his team to Australia in November for their next Test encounter.