Left-handed opening batsman Ayub made a sparkling 101 off 94 balls in a Pakistan total of 308 for nine.
Heinrich Klaasen thrashed 81 off 43 balls for South Africa -– but the hosts were beaten by 36 runs chasing an adjusted target of 308. The match was reduced to 47 overs a side because of rain.
Ayub, 22, hit 113 not out in the second one-day game against Zimbabwe in Bulawayo last month and 109 in the series opener against South Africa in Paarl last week.
In between his one-day appearances he made an unbeaten 98 in the second Twenty20 international against South Africa in Centurion.
In contrast to Ayub’s form, his opening partner Abdullah Shafique was out for his third successive duck after Pakistan were sent in to bat.
But Ayub was seldom troubled as he played shots all around the wicket in partnerships of 114 with Babar Azam (52) and 93 with captain Mohammad Rizwan (53).
Ayub fell to debutant Corbin Bosch, caught behind attempting an audacious flick to leg, after hitting 13 fours and two sixes.
Bosch, the son of the late Test and one-day international player Tertius Bosch, received a call-up after injuries hit South Africa’s fast bowling resources.
For the third successive match, Klaasen was the only South African to make a half-century. He kept South Africa ahead of the required run rate until he was sixth man out, caught on the square leg boundary off Shaheen Shah Afridi with the total on 194 in the 29th over.
Ayub followed up his century by taking one for 34 in 10 overs with his mixture of off-spin and carrom balls, claiming the key wicket of David Miller and producing the most economical figures by any bowler in the match.
Brief scores:
Pakistan 308-9 in 47 overs (Saim Ayub 101, Mohammad Rizwan 53, Babar Azam 52, Salman Agha 48; K. Rabada 3-56) v South Africa 271 in 42 overs (H. Klaasen 81, C. Bosch 40 not out)
Result: Pakistan won by 36 runs (DLS method)
Series: Pakistan won the three-match series 3-0
Toss: South Africa
AFP
