Dean Elgar and Marco Jansen shared a century partnership and stretched South Africa's lead on the third day of the first Test against India at SuperSport Park in Centurion on Thursday.
South Africa were 392 for seven at lunch, a first innings lead of 147.
Elgar took his overnight score of 140 to 185 before he gloved a catch down the leg side off Shardul Thakur.
Elgar and Jansen (72 not out) had batted for two hours in a morning’s play extended to two-and-a-half hours when Elgar fell after a 287-ball innings which included 28 fours.
The pair took South Africa from a narrow 11-run lead at the start to a position of strength.
Elgar and Jansen put on 111 for the sixth wicket.
Having survived a tricky period in fading light before the close on Wednesday, they twice saw off the threat of Jasprit Bumrah and Mohammed Siraj -– at the start of play and later with the second new ball.
The tall Jansen made his second Test half-century and highest score.
He faced 120 balls and hit nine fours and a six.