Pakistan achieved their 103 - run victory target off just 20.5 overs in the last session of the fifth day 's play at the Shere Bangla stadium .
Pakistan won the first Test in Chittagong by an innings and 184 runs .
Pakistan , who won the first Test in Chittagong by an innings and 184 runs , achieved their 103 - run victory target off just 20.5 overs in the last session of the fifth day 's play at the Shere Bangla stadium .