Du Randt, who currently holds a similar position with Super 14 side the Cheetahs, will begin his role in the first international of this year and will continue until after the 2011 World Cup in New Zealand.
A few minor contract details still need to be agreed between both parties but the 37-year-old appears all but certain to return to national colours ahead of this year's Tri Nations.
Du Randt is known to Lions fans for his role in the 1997 series between Britain and Ireland's elite and the Boks.
It may not be high on Du Randts list of favourite memories but Lions fans will never forget the sight of Scott Gibbs bullocking through the giant prop in the stunning second-Test win in Durban 13 years ago.
That iconic moment is seen as one of the most influential in a heroic Lions triumph - one in which they stood up to the huge physical challenge presented by the Boks and severely dented the Afrikaaner image of unrivalled power and strength.