"With the British & Irish Lions heading to South Africa in a just a few months, these Tests are as important as any we have undertaken since our re-admission in 1992," said de Villiers, whose side will take on the Lions in Durban, Cape Town and Johannesburg in less than eight months time.
Following plenty of speculation both at home and abroad, De Villiers has decided to give utility back Piennar a chance to impress as a playmaker having usually been employed at scrum-half or on the wing. If Pienaar's switch to No10 was expected, De Villiers' decision to move Springbok skipper Smit across the scrum has come as more of a surprise, although Smit's power has often led to the possibility being discussed.
"Ruan Pienaar is earmarked for the No 10 jersey as I'm looking to find a long-term successor to Butch James, following his decision to retire following the Lions tour next year.
"We felt that the time is right to give players like Ruan an opportunity and we will be looking at John Smit as a tighthead on this tour."
The Springbok squad will assemble in Cape Town next Tuesday before departing for the UK on Friday, October 31.