Duanne Olivier took 5-53 as the Central Gauteng Lions dismissed the Free State Knights for 124 at the Wanderers on Thursday.
The Proteas fast bowler recorded his second five-wicket haul in as many matches and claimed his 25th wicket of the campaign.
The home side reached stumps on 55-1, only 69 runs behind, with Joshua Richards on 33*.
The Lions, who have won all three their games this season by an innings, began the day with Malusi Siboto taking two early wickets. Jacque Snyman (46) became Siboto’s third victim to leave the visitors on 68-3.
Olivier then found his rhythm to devastating effect, bagging four scalps as he ripped through the Knights middle order.
Olivier and Codi Yusuf then returned to finish the job within 38 overs.
In Paarl, the Northerns Titans were inspired by a fifth first-class century from Neil Brand (111) to post 308 against the Boland Rocks.
Zakhele Qwabe (4-40) was the standout bowler for the hosts.
The day’s second hundred came from the bat of the EP Warriors’ Matthew Breetzke, whose 100 propelled the home side, along with Rudi Second’s 76, to 285-6 against Western Province.
Kyle Simmonds (2-36) was WP’s best bowler.
In Potchefstroom, Marques Ackerman finished the day’s play on 98* as the KZN Dolphins reached stumps on 213-3 against the North West Dragons.
Ackermann partnered with Keegan Petersen for an 86-run third-wicket stand, before the latter was the last wicket to fall for a well-played 54.
4-Day Series Round 4 Day 1 scores:
Central Gauteng Lions trail Free State Knights by 69 runs
Knights: 124 after 37.5 overs; J Snyman 46 (50), G Coetzee 21 (44); D Olivier 5-53, M Siboto 3-28
Lions: 55-1 after 17.1 overs; J Richards 33* (56), D Hendricks 5 (38); P Kruger 1-1
KZN Dolphins lead North West Dragons by 213 runs
Dolphins: 213-3 after 51.3 overs; M Ackerman 98* (124), K Petersen 54 (91); D Potgieter 3-34
Northerns Titans lead Boland Rocks by 308 runs
Titans: 308 after 99.3 overs; N Brand 111 (230), G Cloete 56 (115); Z Qwabe 4-40, H Viljoen 2-77
EP Warriors lead Western Province by 285 runs
Warriors: 285-6 after 97 overs; M Breetzke 100 (202), R Second 76 (136); K Simmonds 2-36, G Kaplan 1-13