Top-seeded Alexander Zverev of Germany beat Matteo Arnaldi of Italy 6-7 (5), 6-3, 6-2 on Thursday night in the third round of the National Bank Open to reach 500 match victories.

Kazakhstan's Elena Rybakina advanced to the National Bank Open semifinals after Ukraine's Marta Kostyuk was forced to retire with an apparent arm injury while trailing 6-1, 2-1 in women's singles action Monday in Montreal.

Alexander Zverev fired a ball into the hazy, evening sky — and right out of Sobeys Stadium in frustration. A few years back, the damage might have been a lot worse. The National Bank Open favourite had just lost the tiebreak in a knife-edged first set off a shot that clipped the net with a semifinal berth on the line.