Top-seeded Alexander Zverev of Germany led Francisco Cerundolo 6-4, 1-0 when the 14th-seeded Argentine retired because of an abdominal injury Saturday night in the National Bank Open. Zverev advanced to face defending champion Alexei Popyrin of Australia in the quarterfinals.

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

Keys, a runner-up at the 2016 tournament in Montreal, matched Ana Ivanovic for the longest gap between quarterfinal appearances at the event in the Open Era. Keys had not made it past the second round in Canada since losing to Simona Halep in that final nine years ago.