Durban - Cameron van der Burgh marked his arrival at the South Africa National Aquatic Championships by topping the 100 metres breaststroke qualifiers and easing into the semi-finals in Durban on Monday.
The world record holder and Olympic gold medallist in the same event swam through in a time of one minute, 2.12 seconds in what was his first swim of the week-long event at the Kings Park Aquatics Centre.
Jared Pike was second quickest in a time of 1:02.62, while Marko Visser (1:03.39) came third.
The April 7-12 nationals are doubling up as the official qualification event for the 2014 Commonwealth Games to be held in Glasgow later this year.
Roland Schoeman was the fastest qualifier in the 50 metres butterfly, racing through in a time of 23.93 seconds.
The veteran Olympian was comfortably ahead of Brett Walsh (24.50), with Willie Scheepers (24.77) third.
South Africa's Chad le Clos, bidding for eight titles this week, also joined them in the semi-finals, although he was only sixth quickest after coming second in his heat behind Scheepers in a time of 24.92.
The 21-year-old was fifth-fastest on his way to reaching the 200 metres freestyle final after a time of 1:51.61.
Calvyn Justus was surprisingly quickest across the distance in a time of 1:49.98 ahead of Myles Brown (1:50.43) and Sebastien Rousseau (1:50.99).
Dylan Bosch was seventh fastest in 1:52.58 with the American-based swimmer Le Clos and Brown having already secured their ticket to Scotland after posting qualifying times on Monday.
On the women's side, Karin Prinsloo, who also joined them on Monday, eased into the 100 metres backstroke and freestyle semis with times of 1:01.64 and 57.20 respectively.
That put the 24-year-old top in the backstroke and second in the free, behind Trudi Maree (57.09).
All swimmers must record the stipulated qualifying times this week if they want to have a chance of making the Team South Africa squad for the Commonwealth Games.