Kane Williamson and Ish Sodhi defied Pakistan bowlers Thursday as New Zealand reached 519-6 at lunch on the fourth day of the first Test in Karachi.
The home team's efforts for early wickets went in vain as Williamson took his overnight score of 105 to 137, and Sodhi was able company on 41.
Resuming on 440-6, New Zealand now lead by 81 runs and are in a good position to take the first Test of the two-match series.
Pakistan took the third new ball with the total on 493-6, but neither the fast bowlers nor the spin duo of Nauman Ali and Abrar Ahmed could break the partnership, which has so far yielded 78 runs.
Williamson reversed a leg-before decision against him from Pakistan umpire Aleem Dar on 116 after television replays showed Nauman's delivery pitched outside the leg stump.
He has so far hit 12 boundaries in his 25th Test century, anchoring the innings after openers Tom Latham (113) and Devon Conway (92) got big scores on Wednesday.
Ahmed is Pakistan's best bowler with 3-172, while Nauman has 2-154.
New Zealand are playing their first Test series in Pakistan for 20 years.