Abu Dhabi: Pakistan, replying to New Zealand's first innings total of 153, were 59-2 at close of play on the opening day of the first Test in Abu Dhabi on Friday.
Haris Sohail (22) and Azhar Ali (10) were at the crease when stumps were drawn as Pakistan are another 94 runs behind New Zealand's total who batted after winning the toss at Sheikh Zayed Stadium.
Earlier, the Kiwis were all out for 153, with Williamson's 27th Test half century reduced to a footnote.
His performance with the bat had lifted New Zealand from 39-3 to 111 before medium pacer Hasan Ali (2-38) and left-arm spinner Haris Sohail (2-11) struck twice each to leave their opponents struggling at Sheikh Zayed Stadium.
Leg-spinner Yasir Shah, who finished as the best bowler with 3-54, dismissed Ajaz Patel for six to end the innings.
Hasan removed Williamson with a slower delivery as the New Zealand skipper went for a hook and gloved the ball for wicketkeeper Sarfraz Ahmed's fourth catch of the innings.
Williamson's 112 ball-63 had five boundaries and he added 72 for the fourth wicket with Henry Nicholls who made 28 with four boundaries.
In the same over Hasan trapped Colin de Grandhomme for a first-ball duck before Sohail dismissed Ish Sodhi (four) and BJ Watling (four) -- both were trapped leg-before.
Mohammad Abbas, who has figures of 2-13, had removed Nicholls, caught behind by Sarfraz soon after lunch.
Pakistan dominated the first session as New Zealand were 81-3 at lunch, with leg-spinner Yasir Shah taking the first of his two wickets in his opening overs.
Yasir had derailed New Zealand's progress in the first session with the wickets of opener Tom Latham (13) and Ross Taylor (two) in his first spell.
New Zealand openers Jeet Raval and Latham survived some anxious moments before pace spearhead Mohammad Abbas had Raval edging to wicketkeeper Sarfraz Ahmed after scoring seven.
Yasir, who had to endure a tough last week due to the death of his mother, had Latham caught at mid-wicket off a loose drive with the fourth ball of his first over.
In his fourth over Yasir had Taylor caught behind with a sharp leg-break, leaving New Zealand at 39-3.
New Zealand handed Test debut to 30-year-old left-arm spinner Ajaz Patel, leaving out pacer Tim Southee.