Marinkovic is another AMD/ATI veteran, he started at ATI in 1996 as Senior ASIC Project Manager. More recently, he's been behind the push in Heterogeneous System Architecture (HSA) and he was one of the key executives behind the overhaul of the AMD graphics driver software.
Here's the official statement from AMD:
"Sasa Marinkovic Director, Radeon Software Marketing will be taking leadership of AMD Product and Content Marketing. Over his twenty years career at AMD, Sasa has successfully launched several generations of disruptive AMD products and will be responsible for the introduction of the next generation of AMD’s Ryzen and Radeon products. In addition, Chris Hook has left AMD to pursue other opportunities. We thank Chris for his many contributions and wish him well in the next stage of his career."