Williamson didn't force the issue but bruised the crimson middle of his bat with strokes all around the wicket despite not finding the boundary until his 58th ball on 26. He will be disappointed not to go on after setting a foundation.
Operation Desert Strip began positively with McCullum and Latham bringing contrasting elements to an opening partnership of 77.
McCullum lost his wicket late in the opening session for 43, succumbing to a trap with a lofted pull shot down the gullet of Shan Masood off right-arm pace bowler Ehsan Adil. The shot wasted a promising start, but incoming batsmen could be reassured runs were plentiful.
McCullum was bravado for the most part and jittery on occasion. Several shots brought 'splat' and 'kapow' comic strip appeal, including dispatches for six over deep mid-wicket and long-on. The former brought indignity for Pakistan; they couldn't find the ball and there was no-one in 'the crowd' to throw it back.
Both openers were subjected to Pakistani close-in fielders regularly stretching their vocal chords with blood-curdling Howzats but nothing looked too convincing.
McCullum also endured the ball of the session from leg spinner Yasir Shah who flighted, drifted and spun one across him to rap his back thigh. The delivery would have missed the stumps, but it was alarming on the first morning.
Latham survived a review for lbw on 11 when the score was 25 but the ball hit too high.
ANDREW ALDERSON TRAVELLED TO THE UAE COURTESY OF EMIRATES.