Knights had to secure a bonus-point victory in their final league game of the Ram Slam Challenge for a home semi-final, but rain intervened and the match was abandoned. They had to share points with the team they will face in that knockout match, Lions, at Wanderers on Sunday.
A rampant 64 off 24 balls from Rilee Rossouw took the total to 186 and had given Knights strong hopes of victory. Knights' rapid scoring though meant there were wickets on offer. The Cobras seamers took six between them, with Kagiso Rabada's 2 for 21 being the pick. Lonwabo Tsotsobe and Chris Morris, though, returned economy rates over 11. Rossouw had given shape to the innings and late blitz from Dillon du Preez - 21 off 6 balls - was the perfect finish.
The Lions chase was cut short at 2.2 overs with lightning flashing around the ground. Soon after the deluge came and wiped out all further chances of play.
Cobras topped the table with eight wins from 10 games, the latest coming through a miserly bowling performance led by Steyn's 1 for 19 in his four overs that kept the opposition to 131. An unbeaten 56 off 51 balls from Amla overhauled the target with nine wickets and 11 balls to spare.
Ryan Bailey's 62 off 41 was the only source of resistance from the Warriors line-up after Steyn and the Cobras seamers struck thrice in seven overs. Yaseen Vallie played second-fiddle in a 95-run partnership for the fourth wicket. But a poor season - they had only three wins from 10 matches - ended with a poor defeat.