Coming off a first-ever loss to Bangladesh in one-day internationals, South Africa's openers gave the side a solid start by adding 58, after captain Hashim Amla won the toss.
Opener Stiaan Van Zyl scored 34 before he was caught behind attempting a leg glance off the bowling of Mahmudullah.
Faf Du Plessis was bating on 33 with Dean Elgar on 30 at the first interval.
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