Port Elizabeth: South Africa's Imran Tahir spun his way through Sri Lanka's middle order to set up an eight-wicket win in the first one-day international at St. George's Park on Saturday.

The legspinner claimed three key victims on his way to figures of 3-26, which helped South Africa bowl its visitors out for 181 in 48.3 overs.

South Africa's batsmen had no problem knocking off the unimpressive target, with Hashim Amla and Faf du Plessis hitting half-centuries as the hosts won with more than 15 overs to spare.

Sri Lanka recorded a Twenty20 series win over a second-string South African side earlier in the week to lift its first ever trophy in the country, but the Proteas were bolstered by the return of five senior players for the five-match ODI series.

That restored the gulf in class that was evident in a 3-0 Test series whitewash for the hosts, who dominated the opening encounter from the start.

After winning the toss and choosing to bowl in cloudy and extremely windy conditions, South Africa picked up two early wickets through fast bowler Wayne Parnell before Tahir took care of the middle order.

Kusal Mendis was the only Sri Lankan batsman able to contend with South Africa's bowlers in the conditions, as he made 62.

Although Mendis rebuilt the innings in a 72-run stand with Dinesh Chandimal (22), Tahir broke the partnership when he bowled Chandimal with a googly and then trapped Mendis lbw shortly after.

When Upul Tharanga also fell to Tahir, Sri Lanka had fallen to 102-5 and the rest of its innings was a struggle.

Dhananjaya de Silva's 28 was the only other score of note, as Parnell struck again and finished with 3-48.

South Africa's chase was set up by a 71-run opening stand between Amla and Quinton de Kock (34), who fell just as the pair were beginning to accelerate.

The left-hander slapped a delivery from Lakshan Sandakan straight to cover, but Amla (57) went on to add a further 60 runs in partnership with Du Plessis.

Amla's dismissal with just 51 runs required for victory gave AB de Villiers another opportunity to reacquaint himself with international batting, and the captain scored an unbeaten 30 at better than a run-a-ball as he saw South Africa home alongside Du Plessis (55 not out).