CAPE TOWN, South Africa (AP):

Saeed Ajmal's 10-wicket match haul proved in vain as South Africa beat Pakistan by four wickets inside four days on Sunday to take an unassailable 2-0 lead in the three-match series.

After their bowlers took Pakistan's last six wickets for just 22 runs in the first two sessions of the day, the Proteas barely looked troubled in chasing 182 to win the second Test at Newlands, despite Ajmal's best efforts.

South Africa have now won their last six series and are unbeaten in 12. They have not lost a five-day match since December 2011 - 14 games ago - and have won their last six on the trot to underline their position as the world's top Test team.

For their part, Pakistan were left to regret an opportunity missed after they had reduced South Africa to 109-5 in the first innings after scoring 338.

"It was one of the more rewarding victories we've had," South Africa captain Graeme Smith said. "It was a really good Test win because we were under a bit of pressure come day three and we needed two days of really big performances, and to get those performances was incredible."

HEAVY WICKET LOSS

The tourists gained only a 12-run lead on first innings, and began day four on 100-3, but soon lost Misbah-ul-Haq when a rush of blood saw his attempt to sweep out of the rough give Robin Peterson one of his five wickets in the match.

"That was the turning point today," Misbah said later. "After that the collapse started."

The Pakistan collapse came after the ball was changed by the umpires during the morning tea break, allowing South Africa's seamers to find lateral movement as the hosts claimed three wickets in three balls to leave Pakistan regretting their inability to post a more challenging target.

"Whenever you are chasing 250 in the last innings and Saeed Ajmal is on, it's very difficult," Misbah said. "If we had another 60 runs, the pressure could have been different."

South Africa deserved credit for their bold brand of cricket on days three and four. They began Saturday with their back to the wall because of Ajmal's five wickets the previous day, but were rewarded for a calculated counter-attack that ensured their final five wickets were worth 217.

SPECIAL MOMENTS

"I think you need to recognise those moments and understand how to play in those moments," Smith said. "We needed to transfer pressure back on to Pakistan and, hopefully, create a bit of a momentum shift.

"We also felt that Ajmal was really effective in the evenings as the wicket got drier, but the morning was maybe the opportunity where we could put him under a bit of pressure."

Peterson's career-best 84 was at the heart of that first-innings revival and he was named Man of the Match for both that innings and his five wickets in the match.