Opener Tamim Iqbal struck an unbeaten half-century to guide Bangladesh to an eight-wicket win over Zimbabwe in the opening match of a tri-nation one-day international tournament at Dhaka today.Tamim struck 84 off 93 balls as Bangladesh cruised to 171-2 in just 28.3 overs. The hosts earlier dispatched Zimbabwe for 170 in 49 overs as left-arm spinner Shakib Al Hasan claimed 3 for 43. Sikandar Raza top-scored for the visitors with 52 as well as taking 2 wickets. Zimbabwe will face Sri Lanka in their next match of the tournament at the same ground on Wednesday.