Wiaan Mulder is in the squad of South Africa as a bowling all-rounder. His batting position was lower middle order in most of the matches (in all formats). You can't expect a lot of runs, fifties and centuries from such position.
As our expectations, South Africa won the second Test match. South African captain Mulder who was batting at 367 runs, he called for the declaration of the innings. He could have reached 400 but he was playing for the team and not for himself.
He took the good decision but if he had completed his own record, so in that case they would still be winning but he played well and the team is winning what else we want? Now it is the time for the Tri-Nation series between them but New Zealand will add on and join them in the T20 series that is going to start from 14 July.