On a perfect day for seeds, No. 1 Jo-Wilfried Tsonga of France, No. 5 Jeremy Chardy of France and No. 7 Kristof Vliegen of Belgium also won in straight sets.
Ferrer was broken in the first game by Sela then had to save three break points in the third just to hold. Then what was living up to a tough draw turned into a rout.
Tsonga hit 11 aces in pasting Thiago Alves of Brazil 6-4, 6-1.
"I have African blood and for me it is very important to be here and help improve the standard of the game here,'' said Tsonga, who reached the 2008 Australian Open final and this year's quarterfinals.
Countryman Chardy dispatched Jiri Vanek of Czech Republic 6-0, 6-4, and Vliegen beat Ross Hutchins of Britain 7-6 (3), 6-4.
Ivo Minar of Czech Republic spoiled South Africa's biggest hope, Kevin Anderson, 7-6 (4), 6-4.
On a rain-interrupted day, other winners included Marco Chiudinelli of Switzerland, Frederico Gil of Portugal, and Denis Istomin of Uzbekistan.
Ferrer wins 12 straight games at SA Tennis Open
Ferrer wins 12 straight games at SA Tennis Open
Juande Ramos Hints At Real Madrid Debut For Faubert