Hashim Amla proved his worth as a limited-overs opening batsman when his century guided South Africa [Images] to a series-clinching 128-run victory over Bangladesh on Sunday.

Amla hit 140 off 135 balls -- his maiden ODI century -- to lead South Africa, who were sent in to bat, to 358 for four.

Amla and captain Graeme Smith [Images], who returned from a prolonged elbow injury to score 65, shared an opening stand of 136 off 146 balls before Jacques Kallis [Images] kept the momentum going with a run-a-ball 49.

AB de Villiers [Images], whose 54 not out came off 27 deliveries, and Albie Morkel, with 37 not out in 13 balls, then put the bowling to the sword in the closing overs to help South Africa soar to their highest ever one-day score against the tourists.

Bangladesh failed to extend themselves in the run-chase, much to the dismay of Smith as they meandered to 230, bowled out in the 50th over after off-spinner Johan Botha took three top-order wickets for just 27 runs.

''It can't be good for the game when a team gives up the chase after losing just three wickets,'' Smith told a news conference.

Bangladesh, 2-0 down in the three-match series after Friday's 61-run loss in Potchefstroom, travel to East London [Images] on Wednesday still looking for their first one-day win in South Africa.