CD have jumped to third place on the table, leapfrogging ND and sending Auckland spiralling to fifth place despite the latter boasting the return of three Black Caps in Colin Munro, Colin de Grandhomme and Lockie Ferguson.
Top qualifiers Wellington Firebirds will host the second-placed Canterbury Kings in the other semifinal after winning by two wickets yesterday while a similar result from the Otago Volts over the Knights didn't help them avoid the wooden spoon.
"It's been a good day, mate," said Young, who carved up a milestone second List A century of 106 not out in helping eclipse the visitors' 237 all out in 43.2 overs with 40 balls to spare.
The skipper forged partnerships with opener Jesse Ryder (54 runs) and No 4 Tom Bruce (70no), after Black Caps maestro Ross Taylor could only add one run at No 3.
"Jesse was playing freely so it was fantastic for me to come in and relax to take my time to score but then we lost Jess and then we lost Roscoe so all of a sudden we were 100 for three and needing another 130-odd runs on quite a slow wicket which could have been tricky," he said.
He need not have fretted as Bruce worked his way in methodically before blunting Auckland's bowling attack for a winning total of 240 runs with 55 balls to spare.
"Brucie hit the winning runs [ a lusty six] and he did it in style," Young said with a chuckle of the big hitter who seemed to have gone into dormancy after his T20 Black Caps debut.
The former New Zealand U19 World Cup captain carved up 15 boundaries at almost a run a ball in his 133-minute occupation.
"It's incredibly rewarding especially because we had our backs against the wall before the last two games. It's a very, very tough ask to say to the boys that if we want to keep our hopes alive then we have got to win the next two games with a bonus point.
"But we have a fantastic bunch of guys who came away with wins and bonus points ... and for me to be able to contribute to that win today with my second hundred is immensely pleasing."
The Aces won the toss and padded up, something CD intended to do but Young took heart from a wicket that was under the covers for 36 hours.
"We knew it was going to be slightly tacky," said the 24-year-old righthander from Taranaki who relished Black Caps seamer Ben Wheeler taking the prized scalp of T20 big hitter Glenn Phillips for a golden duck in the first over.
But it was a false dawn for CD who didn't take another scalp until the the 16th over (Jeet Raval) before the wicket haul began in the 30th over.
"Seth [Rance] came back for his second spell and took wickets in an over and Ajaz bowled very, very well from one end to contain them," he said of red-ball king Patel who finished with the figures of 1-37 from 10 overs, including three maidens, on a doormat where batsmen wipe off bowlers from their shoe sprigs as roadkill.
But the format's top run scorer, George Worker, who could only manage five runs to take his total to 495 in his quest to become the first A Lister to carve up 500 this summer, again showed why Black Caps coach Mike Hesson seriously needs to call him up as an allrounder.
Worker took a milestone 4-22 from six overs, including two maidens, with his left-arm offies to sit third-equal highest wicket taker in one-dayers with 11.
"Georgie was lucky enough to get four wickets," Young said. "To be honest, we were staring down the barrel chasing 350 at one stage."
He saluted his bowling attack for taking on the likes of Raval (46 runs), Sean Solia (60), Munro (62) and De Grandhomme (37).
"We bowled with aggression and looked to take wickets, which was pleasing," he said as the scoreboard reflected a cellphone number-like digits for the remaining six Aces batsmen.
Even Bruce got into the act as a part-time, right-arm offspinner with the prized scalp of Munro as Young dexterously exploited the cross winds.
"We thought Brucie might be able to drift the ball in to Munro and spin it away from Solia and he got Munro, which was fantastic because he's a world-class player," Young said.
It wasn't easy for Malan, assistant coach Ben Smith and Young to drop inform white-ball batsman Joshua Clarkson from the line up to accommodate the injection of Taylor.
"Look, it was a very hard decision but in the end it's one of those things. If Roscoe has time to come back to play for us then we're always going to welcome him with open arms.
"It just means one of the batters has to miss out so, unfortunately, this time it was Josh Clarkson but we've had a chat with Josh and I think he understands.
"He's an essential part of our group and he's had a fantastic two campaigns for us in the Super Smash and Ford Trophy but when Roscoe goes back to the Black Caps Clarkey will be back in the batting order and things will resume as normal with him getting out to smash the sixes he's been doing for us earlier," Young said, adding Clarkson's knocks had been match-defining ones.
He labelled Clarkson a special player, realising it would have been tough for him to run out the drinks.
"He's a man of character so I'm sure he'll take it on the chin and come back even hungrier next time," Young said, unsure how long CD have the services of Taylor or any other Stag before South Africa arrive for their tour.
