South Africa, chasing a target of 268, were cruising on 108 for one after 22 overs when Sami and Hafeez triggered a middle-order collapse as the visitors lost six wickets for just 60 runs.

Four South African batsmen fell in 47 balls as Sami effected two brilliant run-outs fielding inside the circle and Hafeez took three wickets.

South Africa were eventually restricted to 225 for nine in 50 overs, last-wicket pair Alan Dawson (23) and Makhaya Ntini (16) posting an unbeaten partnership of 38.

Opener Hafeez, who has scored just 120 in his last seven matches, bowled 10 overs for 37 runs while Sami returned to wipe up the tail and finish with figures of three for 20.

The hosts won the first match of the series on Friday by eight runs. It was the first time since 1994-95 that Pakistan had recorded back-to-back one-day wins over South Africa, who had won 25 of the last 36 matches between the sides.

South Africa, again without injured opener Herschelle Gibbs, were well served by Boeta Dippenaar who made 58 and Jacques Kallis (42), the pair sharing a second-wicket stand of 89 from 106 balls.

Dippenaar, who carried his bat for 110 on Friday, was joined by Kallis with the total on 19 in the fifth over after skipper Graeme Smith was induced into playing a wild shot outside the off stump by Sami.

Umar Gul, replacing injured leg spinner Mushtaq Ahmed, suffered in particular, with Dippenaar taking 11 runs from one over and Kallis hitting him for three fours in quick succession.

But Hafeez, a part time off spinner, pegged the tourists back by trapping Kallis lbw in the 22nd over.

Sami than struck in successive overs, running out Neil McKenzie and Mark Boucher before Hafeez bowled Dippenaar trying an extravagant sweep to leave South Africa on 138 for five.

Earlier, Ntini, who bowled just three overs on Friday, took four for 46 but it was not enough to stop Pakistan posting a challenging total of 267 for seven.

He took the key wickets of Younis Khan (41), Shoaib Malik (45) and Abdul Razzaq but Pakistan gathered 82 runs from the last 10 overs to set up their victory.

Yousuf Youhana held the top order together with another chanceless knock of 65, his sixth half century in seven innings.