Cricket South Africa confirmed a two-Test tour of Sri Lanka In July along with five One-Day Internationals and a T20I on Wednesday.
Vernon Philander shoots up to No.3 in both -- bowlers and all-rounders -- lists in the latest ICC player rankings.
Smith retained his top spot, while Root and Williamson exchanged places within the top five in the latest ICC Test Rankings.
Both Australia and New Zealand have 102 points but New Zealand lead their trans-Tasman neighbours on decimal points and occupy the third spot.
Philander takes six as South Africa beat Australia by 492 runs in the final Test in Johannesburg, win series by 3-1.
To chase 612, Australia reach stumps on 88/3, needing to bat out the entirety of day five to save the fourth Test in Johannesburg.