None of the Zimbabwe batsmen was able to score quickly with only skipper Brendan Taylor (32 not out) and Vusi Sibanda (31) compiling scores of note in the home total of 135 for five.
Pakistan all-rounder Shahid Afridi used all his guile to bamboozle the Zimbabwe batsmen and his wrist spin brought match-winning figures of three for 25 in four overs.
"Early on it was doing a bit, after six or so overs it was coming on nicely. We wanted to just bat with our top six and so were cautious at the start. We felt that with the bowling attack we have, if we got anything over 150 we could win," Shehzad said at the victory presentation.
Zimbabwe won the toss and elected to field, making a good start after opening the bowling with off-spinner Prosper Utseya conceding only 15 from his four overs.
But all the while Shehzad was blazing away from one end and when he was joined by Afridi (23 from 16 balls) with a little more than five overs to go, Pakistan stepped up the scoring rate. There was also a good cameo from debutant Sohaib Maqsood (26 from 16 balls).
All of the Pakistan bowlers were able to contain the batsmen in the Zimbabwe reply, with Afridi in particular using his variations to great effect on a dry, lifeless pitch.
The second Twenty20 will be played at the same venue on Saturday.
(Reporting By Nick Said in Cape Town; Editing by John Mehaffey)
