Another five-setter for second seed Alexander Zverev facing Russia's Karen Khachanov, who took the much-fancied German all the way before succumbing.
Zverev is into his first grand slam quarter-final.
Another young gun, Austria's Dominic Thiem, will play him after he needed four sets to dispose of Japan's Kei Nishikori. The pretenders will be aware that formidable obstacles remain.
Novak Djokovic eased past Fernando Verdasco, no mug on clay, but unable to trouble the Serb, tumbling to a straight-sets loss, Djokovic's 200th win on the surface.
World number 72 Marco Cecchinato continued his dream run, becoming the lowest ranked player in a decade to reach the quarters here, beating David Goffin. His reward? Djokovic next up.