Northern were well-placed to tally a huge total after 13 overs, sitting on 111-3 with Scott Styris and BJ Watling at the crease, and a wealth of batting to follow. But the Nelson proved unlucky for the men in pink, as the Stags picked up Styris, Watling and the key wicket of Dan Vettori in the space of two overs.
From there, the crafty Pete McGlashan utilised his full bag of tricks to haul his side toward a good total but the Knights made a complete hash of the final over, losing three wickets for only three runs.
Thankfully for Northern Districts, the jitters which concluded their innings appeared to spill over to the home side's turn with the bat. Once Styris won a personal duel with Ross Taylor to send the Black Caps captain back to the sheds for a duck, Central were teetering at 32-3 after seven.
But just when the Knights were cruising to a vital four points, Doug Bracewell and Matt Sinclair came together to provide hope for the Stags. Some lofty hitting from Bracewell led to a succession of big overs and left 62 needed from the final five.
That's when Southee and Boult proceeded to put on a clinic in death bowling, combining to concede just 38 runs from the remaining overs. Southee bowled Bracewell for 37 in the penultimate over, Boult repeated the dose to send Sinclair packing for 63, and the Knights stayed in the hunt for the T20 title.