Needing two, Kain hit Chris Martin's penultimate ball for four.
"I was just really determined to have a shot at it," Mason said. "There's always a chance at Puke[kura Park] because of the small boundaries.
"The adrenaline was flowing so I just watched the ball hard, gave it a go and it turned out all right."
All right? More like, 'Yeah, right'.
Mason was raised in Mangatainoka, famous only for a brewery, and the beers would have been on him last night. His 41 not out complemented his 3-52. His improbable allround display left Auckland bereft.
You couldn't say they deserved to win because CD passed their total, but they'd done everything required bar close the deal.
Mason, 37, might have provided the Boy's Own finish, but for the great majority of the match it appeared Parlane would be the unlikeliest of heroes.
It took the chunky right-hander 12 years to score his first domestic limited-overs century and just four days to take his total from one to three.
The 33-year-old, who made his 50-over debut for Northern Districts in 1997, became the first Aucklander to score back-to-back List A tons.
He would not have been there if it were not for the remarkable turnover of players Auckland coach Paul Strang has had to manipulate and manage. Just four players at New Plymouth yesterday played in last month's HRV Cup final.
Their best batsman, Martin Guptill, is on international duty and their best bowler, Andre Adams, cut a track for the riches of the newly formed Bangladeshi T20 league. Handy cast members such as Kyle Mills, Michael Bates, Colin de Grandhomme and Roneel Hira were called up for New Zealand and star import Azhar Mahmood was on a T20 contract only.
Auckland had to rely on a couple of seasoned pros in Chris Martin and Gareth Hopkins, allied to a collection of journeymen and those whose promise is yet to be fully realised.
Parlane fits into the former category, having travelled north this season after failing to land a contract for Wellington, the team he had represented since the 2002-03 season. He didn't score enough early season four-day runs to establish himself, but Strang asked Parlane to come in and do a job in the Ford Trophy major semifinal and final and he scored 223 runs in 227 balls.
Job done.
Parlane's 133-ball 106 yesterday was not without luck. The normally reliable Kruger van Wyk dropped a sitter before he had reached double figures, something he would have been acutely aware of when he strode out to bat when Central Districts were in tatters at 35-3.
McClenaghan had done all the damage, removing the dangerous Jamie How and Mathew Sinclair for 12 and 2 respectively.
Van Wyk (66) and Dean Robinson (63) embarked on a rescue mission but that petered out before Mason and Kain's intervention.
Auckland remain in the hunt for the Plunket Shield, sitting in second behind Northern Districts.
"We'll have a couple of quiets and review this, but we've got to get straight back up again," captain Hopkins said. "We've got a four-day competition to win."
A double would cap a remarkable year for Strang and his many and varied players, but they'll always feel they should have had more.
