Defending champions Waitakere United will face Team Wellington in football's ASB Premiership grand final, although the date of the game remains up in the air.
Both sides caused upsets in their semifinal second leg showdowns today and the final was pencilled in for next Sunday.
But with the first leg of Auckland City's O-League final now scheduled to take place in Auckland the same day, a move to Saturday or the following week is being investigated by New Zealand Football.
Waitakere booked a finals berth after thrashing Canterbury 5-2 in Christchurch to claim a 5-3 aggregate semi-final win and join Team Wellington who added to their 1-0 first leg home win with a 3-1 win at Kiwitea Street to progress to the grand final 4-1 on aggregate.
After last week's 1-0 home loss to Canterbury, Waitakere took just 12 minutes of the return leg to level the aggregate scores with Ryan de Vries slipping past Tom Schwarz and Daniel Glozier before firing a superb shot past Adam Highfield.
Canterbury bounced back within two minutes when Aaron Clapham equalised and the Dragons snatched the lead when golden boot winner George Slefendorfas notched a goal on the half hour mark to give the home side what seemed a comfortable two goal cushion.
But two Waitakere goals inside one minute just after the restart threw the semi-final wide open.
Waitakere United skipper Jake Butler started the fight back when he nodded home a Ross McKenzie free kick. Just seconds later Roy Krishna put the defending champions in front when he latched into a short back pass by Mark Johnston to make it 3-2 on the day, and ahead on away goals with the aggregate scores tied at 3-3.
Roy Krishna extended the lead when he smashed home a Sean Lovemore cross on 63 minutes before Canterbury United were reduced to ten men when Mark Johnston was sent off for dissent with six minutes to go.
The home side's misery was completed when de Vries hit a fifth for the visitors to confirm their finals berth and a 5-3 aggregate victory.
Canterbury United's defeat means Waitakere United or Team Wellington will snare New Zealand's second O-League spot for next season, with minor premiers Auckland City claiming the other.
There was plenty of drama at Kiwitea Street.
Trailing 1-0 after the first leg, Auckland City fell further behind when Henry Fa'arodo latched on to a short David Mulligan back pass to fire home beyond a stranded Jacob Spoonley on 25 minutes of their semi-final with Team Wellington.
But while Wellington finished in the ascendancy in the first half, Auckland shifted gears in the second and pinned the visitors in their own half striking the post three times, before Manel Exposito bundled home a close range header on 71 minutes.
Auckland City's joy was short lived when Dakota Lucas scored with a tap in on 82 minutes with Exposito sent off by referee Chris Kerr after an altercation ensued following the goal.
Lucas capped off a fine individual display with a second goal on full time to give Wellington a comfortable 4-1 aggregate win and a second grand final appearance in eight seasons.
Auckland's season continues as they face two huge matches with Tahitian champions AS Tefana in the OFC Champions League Final, the first leg at Kiwitea Street, followed by a crunch second leg decider in French Polynesia on May 13.