Finland's Emil Ruusuvuori cruised past top-seeded Aslan Karatsev of Russia 7-6 (6), 6-4 to headline Thursday's Round of 16 winners at the Astana Open in Nur-Sultan, Kazakhstan.
Other upset victims included No. 3 Dusan Lajovic and No. 4 Filip Krajinovic, both of Serbia, who lost to Soonwoo Kwon and James Duckworth, respectively. Kwon, of South Korea, prevailed 7-5, 6-4, while Australia's Duckworth won 7-6 (2), 6-3.
Home-court hero and No. 2 seed Alexander Bublik suffered no such fate, winning 2-6, 6-3, 7-5 vs. Miomir Kecmanovic of Serbia.
Marcos Giron upended Australia's Alex de Minaur 7-5, 7-6 (5) to advance to the quarterfinals of the Moselle Open in Metz, France. Minaur was seeded fourth, but he was undone on first serves, 37-27.
Giron will face Peter Gojowczyk in the quarters. The German dumped seventh-seeded Karen Khachanov of Russia 6-3, 7-6 (2).
Other winners included top-seeded Hubert Hurkacz of Poland (6-2, 6-3 vs. Lucas Pouille), No. 3 Gael Monfils (7-6 (2), 6-4 vs. Philipp Kohlschreiber) and Nikoloz Basilashvili (0-6, 6-4, 7-6 (4) vs. Alejandro Davidovich Fokina).
--Field Level Media