Marčinko broke for 3-1 and again for 7-5, outlasting Waltert in a deuce-laden set that swung on two decisive breaks.
Waltert broke for 5-4 after Marčinko saved two of three break points, then held for 6-4 saving all three to seize control.
Waltert broke for 3-2 and again for 5-2, then held for 6-2 saving both break points to clinch the match with clinical precision.