With a first innings lead of 326 runs, South Africa enforced the follow-on despite fast bowler Anrich Nortje being out of action with a groin injury.

Tall left-armer Jansen struck with his first ball of the innings when he had nightwatchman Scott Boland caught behind in the second over of the day.

He followed up with the wickets of Travis Head, Matt Renshaw, Alex Carey and Beau Webster as Australia collapsed.

Steve Smith, who twice needed treatment for what appeared to be a neck injury, top-scored for Australia with 28 before being bowled by Wiaan Mulder.

Brief scores:

South Africa 425-9 declared.

Australia 99 (K. Rabada 2-33, M. Jansen 5-33, W. Mulder 2-14).

Match situation: South Africa lead by 326 runs on the first innings and have enforced the follow-on.

Toss: Australia