Table toppers the Cape Cobras were in control against the Knights as they went in search of the domestic series trophy on the first-day of the last matches of the first-class season in Bloemfontein on Thursday.
The Knights, who lost the toss and were sent in to bat, were dismissed for 191 runs, anchored by top-order batsman Rilee Rossouw, who made 59 runs.
Beuran Hendricks returned four for 50 to lead the Cobras attack.
In response, opening batsman Richard Levi laid the foundation for the visitors with an unbeaten 61 as he guided them to 104 for one, trailing by 87 runs in their first innings when stumps were drawn.
Stiaan van Zyl, also at the crease, was on 29 not out.
Meanwhile, the Warriors and the Highveld Lions, the only other teams with a chance to clinch the title, were locked in a low-scoring battle in Port Elizabeth.
Andrew Birch, who took four for 30, spearheaded the Warriors attack after the Lions won the toss and chose to bat.
Veteran Neil McKenzie put up a fighting 46 to carry the visitors, but they struggled against a defiant bowling lineup as they were dismissed for 157 runs in the final session.
Warriors openers Michael Price and Davy Jacobs were both dismissed after getting early starts, and they were 93 runs behind with seven wickets in hand at the close of play, called five overs early due to a water-logged field in the morning session.
In Centurion, the Dolphins were in complete control against the Titans, with Vaughn van Jaarsveld smashing 101 runs off 110-balls as they coasted to 326 for six.
The home side's bowling attack struggled to break partnerships as they were left on the back foot.
Imraan Khan, Cody Chetty and Jonathan Vandiar all contributed towards the Dolphins' cause, making more than 40 runs each, as they put up a solid stand.