A formidable South Africa thrashed Bangladesh by 206-runs in their final group B encounter of the World Cup at the Sher-e-Bangla National Stadium in Dhaka on Saturday.

- Scorecard

Chasing a stiff target of 285, Bangladesh were shot out for a paltry 78 in 28 overs. This was Bangladesh's second score of under 100 after they were bowled out for 58 against West Indies in an earlier group league game.

After South Africa's total (284 for eight in 50 overs) was aided by three half-centuries from Hashim Amla (51), Jacques Kallis (69) and Francois du Plessis (52), Lonwabo Tsotsobe (3 for 14) blazed through the top-order.

He began the rout by picking up Tamim Iqbal (5), Imrul Kayes (4) and Shahriar Nafees (5) before Smith took a great low catch off Robin Peterson's first ball to dismiss Mushfiqur Rahim (3) as the Tigers plunged to 36 for five in the 16th over.

Skipper Shakib Al Hasan's 30 was the only double-digit score of the innings, with Peterson picking up three wickets as the Tigers were crushed out for only 78 all out in 28 overs.

South Africa's batting was a proficient routine -- Hashim Amla, Kallis and Du Plessis recording solid half-centuries. And just as the Bangladesh bowlers almost got the run flow under control, Robin Peterson and Johan Botha snatched away that glimmer of hope with a flurry of boundaries towards the end.

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But it was the Graeme Smith-Amla opening partnership that laid the foundation for the big score on a slow and low track.

The two put on 98 for the first wicket, Smith coming back to some form with his steady 45 off 68 balls. There was hardly a ball that found the edge or beat the bat with Shakib desperately shifting his bowlers in a bid to unsettle the pair early on.

Then, off-spinner, Mahmudullah Riyad, had Smith stumped in the 21st over with Amla following in the next over bowled by left-arm spinner Abdur Razzak.

Amla's fluent knock had some attractive cover drives -- the right-hander making 51 off 59 balls with the help of six boundaries.

After Jean-Paul Duminy gloved one to wicketkeeper Rahim, Kallis and Du Plessis added 87 for the fifth wicket before both batsmen fell early during the third Powerplay.

Kallis was his typical classic self, hammering five boundaries and a six in his 76-ball knock of 69.

Du Plessis too played a solid hand, making a run-a-ball 52 with the help of a six and four boundaries. At the other end Peterson smashed four boundaries in a short time during his 9-ball 22.

For Bangladesh, Rubel Hossain took three for 56 while Shakib picked up two wickets and there was one each for Razzak and Riyad.