Zimbabwe 256 and 28 for 1 trail South Africa 397 (Du Plessis 98, de Kock 81, Nyumbu 5-157) by 113 runs
Scorecard and ball-by-ball details
The Harare crowd had to resort to song and dance to amuse themselves for large parts of the day and was grateful to offspinner John Nyumbu when his five-wicket haul, the second by a Zimbabwean on debut, ended a decidedly slow South African innings. Faf du Plessis' marathon ended two short of a hundred and Quinton de Kock displayed mettle for his 81 as South Africa pulled into the lead, but after both batsmen were dismissed, the activity on the field paled to that off it.
The second session yielded 56 runs in 30.4 overs as Zimbabwe continued with their ploy of playing on the batsman's patience. The seamers preferred discipline over variation. There were no bouncers, perhaps they thought they didn't have enough pace. The pitch was worn enough to offer variable bounce but Brendan Taylor's host of short midwickets and short covers were kept waiting as the batsmen stuck to stonewalling.
Against Nyumbu, however, the close catchers were in play. He cajoled the rough to yield turn and bounce to threaten both edges of the bat. He lured Du Plessis into a leg-side trap, forced JP Duminy to mistime a reverse sweep to slip and bested Dale Steyn's intent to attack.
Zimbabwe had to negotiate a tricky 13 overs before stumps and Morne Morkel, who was not shy of targeting the batsman's throat, had Hamilton Masakadza fending to third slip to further South Africa's reputation as the past decade's most successful touring team.
To that effect, consolidation was paramount when the day began. Du Plessis progressed in typical fashion, waiting as long as necessary for the bad ball. He ventured outside off only when it was short and wide - Tiripano was slashed over the cordon - or when it was too full - Nyumbu was caressed through extra cover. He was South Africa's anchor at No.3 and he would not budge from that role until a little extra bounce became his undoing. He nipped down the track and tried to smother it, but the tickle reached Regis Chakabva at backward short leg to end his 356-minute stay.
De Kock's nemesis was spin, specifically his inclination to close the face and hit against the turn when Nyumbu tossed the ball up, but he was able to put the threat aside and be the instigator. He was nimble on his feet and raced down to lift Nyumbu for a six, his first boundary of the morning, to reach his fifty. A less certain inside edge to the fine-leg boundary took South Africa ahead of Zimbabwe's 256.
Spin threatened for 12 overs after lunch, but cost 41 runs. De Kock favoured the back foot and put aside the balls that misbehaved until he skewed an inside-edge to short midwicket to hand slow left-armer Sean Williams a first Test wicket. There was enough help for Taylor to persist with spin, but Zimbabwe did not like the pace of scoring.
They dragged South Africa back by employing Tinashe Panyangara, who did not concede a boundary in his 30 overs for 39 runs, and Tendai Chatara who was equally miserly with 27-12-34-1. JP Duminy, newly saddled at No. 7 and with six runs off 123 balls in his last Test, did little to put them off as South Africa scored 15 runs in the 18.4 overs leading to tea.
Steyn's two sixes broke the monotony and helped South Africa to 30 runs in five overs after the break. Duminy updated his resume with his sixth half-century and tried to push on but an ill-advised reverse sweep gave Nyumbu his fifth wicket and a slice of history.
Alagappan Muthu is a sub-editor at ESPNcricinfo