Hyeon Chung claims semi-final place at NextGen ATP Finals in Milan
Hyeon Chung claimed the first semi-final place at the NextGen ATP Finals in Milan with a surprise win over top seed Andrey Rublev.
The Korean overcame the Russian world number 37 4-0 4-1 4-3 to guarantee one of the top two spots in Group A.
Rublev, who has a 1-1 record in the event, will get another chance to make progress when he faces Canadian Denis Shapovalov in his final group match.
Shapovalov maintained his own hopes with a 4-1 4-1 3-4 4-3 victory over Italian wildcard Gianluigi Quinzi.
Croatia's Borna Coric claimed his second win in Group B with a 4-3 2-4 4-1 4-2 success over Russian Daniil Medvedev.
Karen Khachanov reignited his campaign after an opening loss to fellow Russian Medvedev with a 4-1 4-3 4-2 defeat of American Jared Donaldson.