Auckland's second victory of this year's competition moves them into second in the standings, trailing only Central Districts at the halfway mark, though two other matches are still in progress.
The most pertinent of those matches is at University Oval in Dunedin, where a draw is both the likely result and the preferred outcome for Auckland.
Heading into tomorrow's final day third-placed Otago have a 15-run lead over CD with nine wickets in hand, meaning only a sporting declaration or something special with the ball will force a result.
After Otago had piled on 427 in their first innings, the Stags resumed this morning on 115-1 before yet another century from Mathew Sinclair saw his side take a slim lead.
Sinclair's 36th first class ton pushed him past Stephen Fleming and Ken Rutherford to sixth on New Zealand's all-time list and capitalised on a good foundation laid by Jamie How (64) and Carl Cachopa (55).
Otago's bowlers were taking regular wickets at the other end, but Sinclair remained unmoved until Neil Wagner snuck one through the 37-year-old's defences to dismiss him for 142.
CD was soon back in the pavilion with a lead of 22 and, despite Otago opener Hamish Rutherford falling late in the day, a victory appears out of reach for either side.
Elsewhere, Northern Districts will fancy their chances of securing maximum points against Wellington after forcing the hosts to follow on at Karori Park.
With all of day two being washed out, the Knights' bowlers made up for lost time today and left Wellington holding a slim seven-run lead with four wickets in hand.
A five-wicket bag from Tim Southee saw the Firebirds dismissed for 206, with wicketkeeper Luke Ronchi's (113) second century of the season the highlight.
Wellington were sent back into bat still 197 runs in arrears and two early wickets from Brent Arnel had the hosts in early trouble. Once Southee dismissed Jesse Ryder (9) for the second time in the match, Wellington were reduced to 32-3.
Spinner Ish Sodhi grabbed three late scalps to leave Ronchi (62no) and Scott Kuggeleijn (6no) with a battle on their hands to save the match.