Summary Gazi took 3-145 in the first innings.
Sohag Gazi claimed six wickets in his test debut as the West Indies was bundled out for 273 before lunch Friday on the fifth and final day of the first test against Bangladesh.
Chasing a victory target of 245 runs, Bangladesh lost two wickets early to go to the interval at 45-2 in reply.
Opener Tamim Iqbal was out for 5, while his partner Junaid Siddique was removed for 20.
Shahriar Nafees was unbeaten on 19 at the break with Naeem Islam yet to score.
The West Indies struggled from the beginning after resuming on the overnight score of 244-6 and lost its remaining four wickets in quick succession to Gazi (6-74), who conceded only 11 runs.
Bangladesh has two full sessions to reach the winning target and win just its fourth match since becoming a test-playing nation 12 years ago.
The 21-year-old Gazi, who was described by selectors as a "genuine" offspinner, first claimed skipper Darren Sammy for 16 and found himself on a hat trick after bowling Ravi Rampaul for 5 and Tino Best for a duck with the West Indies on 265-9. His final delivery of the day trapped Shivnarine Chanderpaul lbw for 1 to end the West Indies' innings.
Gazi took 3-145 in the first innings.
