They are now 42 points behind Canterbury in the standings after the Wizards completed a victory they would have expected after dismissing Northern Districts for 176 in the first innings in Christchurch.
The Knights enjoyed a 53-run partnership between Jono Boult and James Baker for the 10th wicket on day four but that only delayed the inevitable, giving Canterbury ample opportunity to chase down the 159 runs required.
While there would have been some jitters when they were reduced to 15-2, Dean Brownlie hit 64 to see Canterbury home with an hour to spare.
In Invercargill, a match which seemed headed for a draw at the start of play ended with an Otago batting collapse that gave Wellington a comfortable victory.
Resuming on 480-8 in their first innings Wellington added only seven runs to their overnight score to take a 148-run lead.
Otago seemed to be settling into their work of batting out the day, reaching 92 before the first wicket fell, but they lost four wickets for 12 runs to slip to 133-5. Jesse Ryder, who made 83 in his first knock, was trapped in front by Jeetan Patel for five as the spinner scythed through the top order with figures of 4-75.
After Otago were dismissed for 229, Wellington chased down the target of 82 for just two wickets lost.