South Africa captain Temba Bavuma and Reeza Hendricks starred as the Proteas overpowered Ireland in the third and final T20 international at Stormont on Saturday to seal a 3-0 series win.
The pair's first-wicket partnership of 127 set up a 49-run victory.
David Miller chipped in with an unbeaten 36 as South Africs posted 189-2 from their 20 overs.
It was a total that was too much for Ireland, who finished on 140-9.
Ireland captain Andy Balbirnie top-scored with 27 while George Linde, Wiaan Mulder and Lizaad Williams all took two wickets each for South Africa.