Wessels smashed nine sixes in his 55 off just 18 balls to set the Outlaws on their way to overhauling a 192 target with 11 balls to spare.
Three more came in an over from former Nottinghamshire paceman Andy Carter and the first three deliveries of Pat Brown’s opening over also received the same treatment.
When he finally perished, caught on the deep square leg boundary off Brown – the competition’s leading wicket-taker – the Outlaws total stood on 72 in just the fifth over.
His boundary clearing spree took the pressure off the other Outlaws batsmen as victory strengthened their chances of a top four spot.
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But the Rapids, already guaranteed a quarter-final place, are now involved in a three horse race with Durham Jets and Lancashire Lightning to secure a home tie in the knockout stages.
The Rapids innings of 191-6 was based around a career best T20 performance with the bat by Brett D’Oliveira who hit 64.
The home side were put into bat and Luke Fletcher bowled a testing opening over in which Joe Clarke twice edged him for four.
Clarke produced more convincing shots in clipping Fletcher through mid wicket and carving him over point for boundaries.
Rapids captain Moeen Ali, released by England from Test duty to play in this fixture, got into his stride with two sixes over mid wicket off Outlaws skipper Dan Christian.
The Rapids half century came up in the fifth over but then three wickets fell in quick succession.
Clarke (29) lofted Fletcher straight to Alex Hales at mid-on and in the same over Callum Ferguson (4), a century-maker in the Blast fixture at Trent Bridge last weekend, cut the ball into the hands of Samit Patel at point.
It became 62-3 when Moeen carved a delivery from Steven Mullaney to Jake Libby on the cover boundary.
D’Oliveira and Ben Cox added 52 in five overs before the Rapids wicket-keeper on 16 was caught on the square leg boundary off Mullaney.
Christian returned to the attack to bowl Ross Whiteley (16) and D’Oliveira, having struck three sixes and six fours in his 37 ball knock, departed in the same fashion to Harry Gurney.
But some late aggression from Wayne Parnell, including successive sixes off the final two deliveries of the innings from Gurney, lifted the Rapids to a competitive looking total.
When Nottinghamshire launched their reply, Wessels adapted an all out aggressive approach despite Hales (9) quickly departing to Carter.
After his eventual dismissal, Libby and Steven Mullaney were able to play without taking any risks in adding 49 in six overs.
Brown claimed a second scalp when Mullaney (20) skied the ball on the on side and then Jake Libby (37) was run out after smart work by D’Oliveira after Tom Moores called him through for a single.
But Moores (30) ensured there were no late scares for the Outlaws as he lofted Mooen for three sixes in the 15th over despite him becoming a third victim of Brown.