Scotland spinner Haq went into the clash at the Grange level with John Blain on 41 one-day international wickets and he shattered that record as he dismissed three Pakistan batsmen to move himself clear on 43.
However his efforts were in vain as Pakistan, who won the toss and chose to bat, made 231 for seven and then bowled out Scotland for just 135.
Pakistan were using the fixture as a warm-up for their Champions Trophy campaign, which begins against the West Indies at the Oval in London on June 7.
And the tourists enjoyed some useful batting pratice as captain Misbah-ul-Haq top-scored with 83 not out, while opener Imran Farhat made 49.
Saeed Ajmal and Junaid Khan both took three wickets for Pakistan as Scotland were skittled up in reply.
Nasir Jamshed went for 20 before Scotland's Haq claimed his first wicket of the day when Josh Davey caught Mohammad Hafeez at backward point.
Farhat moved to the brink of a half-century, only to be bowled by spinner Matt Machan when he miscued an attempted slog.
Haq claimed the wickets of Asad Shafiq for seven and Umar Amin for three, before Kamran Akmal fell lbw to Neil Carter for 12.
Misbah and Ajmal steadied the boat with a 51-run partnership for the seventh wicket, but the latter fell for 28 when he misjudged a scoop shot off Iain Wardlaw and the ball skidded into his stumps.
The match had been Northamptonshire batsman Kyle Coetzer's first as Scotland skipper after he was named Gordon Drummond's replacement earlier this week.
And he led by example as he top scored for the home side with 32.
But in the end it proved to be a simple job for Pakistan to rattle through Scotland's lower order, with Rob Taylor falling at the death as Ajmal claimed another lbw.
The teams will meet again in the second leg of their one-day international double-header on Sunday. (AFP)
