Kallis, left, retired hurt with just 16 runs needed for victory [AFP]

Paceman Lonwabo Tsotsobe took four wickets and Jacques Kallis hit an unbeaten fifty to help a disciplined South Africa down Pakistan by eight wickets in the first one-day match.

Tsotsobe took a career-best 4-27 off his ten tight overs on Friday to trigger a middle-order collapse and helped South Africa dismiss Pakistan for 203 before Kallis (66 retired hurt) saw off the target with 9.3 overs to spare.

The modest target was never beyond South Africa's reach after Pakistan batsmen once again failed to take advantage of a good start on a flat Abu Dhabi Stadium, much to the disappointment of a 10,000-strong crowd.

The 35-year-old Kallis, back after missing the limited over series against Zimbabwe at home and South Africa's 2-0 win in the Twenty20 series which finished here on Wednesday due to injury, was at his usual best.

He steadied the South African innings through a solid 77-run stand with AB de Villiers, who also hit an attractive 51, after Graeme Smith (18) retired due to a finger injury and Hashim Amla was dismissed for a well-made 35.

Five boundaries

Kallis, who hit five boundaries and a six off paceman Abdul Razzaq, added another 41 runs with Jean-Paul Duminy (10 not out) to give South Africa a 1-0 lead in the five-match series.

With just 16 needed for win Kallis suffered cramps and retired.

"At one point Pakistan was well set at 140-1 but the bowlers stuck to their task and got us nine wickets for 63 runs and that proved decisive," he said Botha, singling out man-of-the-match Tsotsobe.

Tsotsobe, who took five wickets in the two Twenty20 matches, rocked the Pakistan middle-order with a burst of three wickets off just nine balls during his second four-over spell.

His effort, backed by disciplined spin bowling by Botha (2-40), derailed Pakistan after Mohammad Hafeez (68) and returning Younis Khan (54) put on 114 for the second wicket.

Tsotsobe removed opener Asad Shafiq (19) in the eighth over before Younis joined Hafeez. Hafeez hit seven boundaries during his 84-ball sixth one-day fifty before cutting Botha straight into the hands of Charl Langeveldt.

Four overs later, Younis was trapped leg-before by Botha. Younis hit two boundaries during his 75-ball knock.

Tsotsobe's triple strike followed as he removed Misbah-ul-Haq (14), Shahid Afridi (one) and Abdul Razzaq (two) to complete Pakistan's slide.

"We had just one good partnership and then a middle order collapse, like we had in the Twenty20s, so we need to lift our batting because South Afica will get tougher and tougher," Pakistan's Younis said.

The second match of the series will take place in Abu Dhabi on Sunday.