Captain Tim Southee has declared New Zealand's first innings closed at 580/4, after watching Kane Williamson and Henry Nicholls both bring up double centuries against Sri Lanka on the second day of the second test at Wellington.
At stumps, the tourists were in a spot of bother at 26/2, still 554 runs behind.
Williamson recorded his 28th test ton - and sixth double - before he was caught off spinner Prabath Jayasuriya for 215. He and Nicholls combined for a 363-run third wicket stand that has put the home team in a commanding position.
Daryl Mitchell came and went, caught and bowled by Kasun Raijtah for 17, as the Blackcaps looked for quick runs, before Nicholls reached his maiden double century and his captain pulled the pin.
The performance was much-needed for Nicholls, who has struggled for runs in recent tests. The innings is his fourth test century at the Basin Reserve, continuing his love affair with the Wellington ground.
Fresh from his first-test heroics, Williamson was at his technical best, unleashing with sixes off consecutive deliveries during one Jayasuriya over on his way to triple figures off 172 balls, including 14 boundaries.
He needed only 113 balls for his next hundred, adding eight more boundaries and two sixes.
After starting the day at 155/2 - in large part thanks to opener Devon Conway's 78 - the Blackcaps added 149 runs during Saturday's first session and another 139 in the afternoon.
Nicholls and wicketkeeper Tom Blundell added 50 runs off 34 balls for the fifth wicket, before the declaration.
Opener Oshada Fernando fell, when he edged Matt Henry to Blundell in the 10th over of Sri Lanka's reply, while Kusal Mendis lasted only 10 balls, before he was caught by Conway, as Doug Bracewell celebrated his recall to the NZ test set-up.
Southee was able to call on cousins Doug and Michael Bracewell to bowl in tandem, nightwatchman Prabath Jayasuriya surviving to stumps, with opener Dimuth Karunaratne (16no).
With the Blackcaps ahead 1-0, the Sri Lankans must win to salvage a drawn series, which would be their first in New Zealand since 2006.
NZ 580/4d (Williamson 215, Nicholls 200no, Conway 78; Rajitha 2/126) Sri Lanka 26/2 (Karunaratne 16no, Jayasuriya 4no)
NZ lead by 554 runs