06:00 CET - The final match of the night ended at around midnight local time, but Karen Khachanov is the one who comes out victorious. The 11th seed gets past Alex Michelsen 6-4, 7-6 (3) in a close contest to make the semi-finals in Toronto.
03:45 CET - Two more quarter-finals are complete. In Toronto, Alexander Zverev battles back from a set down to defeat Alexei Popyrin 6-7 (8), 6-4, 6-3. The German is into the semi-finals, where he will face the winner of the other match tonight between Alex Michelsen and Karen Khachanov.
In Montreal, Victoria Mboko's magical week continues. The Canadian triumphed 6-4, 6-2 over Jessica Bouzas Mineiro to qualify for her first WTA 1000 semi-final.
01:05 CET - It is unfortunately a premature end to the first quarter-final as Marta Kostyuk is forced to retire against Elena Rybakina. The Kazakh led 6-1, 2-1, and was in control. However, the Ukrainian could not continue. That allows the number nine seed to move on.
23:43 CET - Play will get underway in Montreal in about 15 minutes time, with Elena Rybakina taking on Marta Kostyuk as both players eye a spot in the semi-finals!
20:50 CET - Hello and welcome to a big night of ATP and WTA quarter-final action from Toronto and Montreal!
With the top two seeds Iga Swiatek and Coco Gauff out of Montreal, the draw has opened up nicely for the final eight.
The highest seed left in the tournament is ninth seed, Elena Rybakina, and the Kazakhstan player will fancy her chances of claiming the title after dropping just one set so far in Montreal. She is up first tonight against Ukraine's Marta Kostyuk from 00:00 CET to get a great night of action underway.
That is followed by the exciting 18-year-old Victoria Mboko, who, high on confidence after her shock victory against Gauff in the last round, takes on Spain's Jessica Bouzas Maneiro in the second and last match of the night.
Over in Toronto and top seed Alexander Zverev takes on the defending champion Alexei Popyrin from 01:00 CET in a fascinating and must-win clash for the German as he looks to remind the tennis world why he is the world number three.
That clash is followed by emerging talent Alex Michelsen against Karen Khachanov, with the latter surprising Casper Ruud in the previous round to end his recent rut against top 20 players.
Follow both quarter-finals from Montreal here and the two Toronto quarter-finals here.