Elina Svitolina kept her tile defence on track by ousting British No.1 Johanna Konta while five former grand slam champions were dumped from the competition on day four of the Rogers Cup.

Svitolina, the No.5 seed and reigning champion, made short work of her third-round clash with Konta in Montreal, scoring a 6-3, 6-4 victory after 85 minutes on court.

The Ukrainian rallied from a break down in the second set to win the last four games on the bounce and seal her fourth straight win against the British player.

Konta was playing her second match of the day, having earlier dismissed former Australian Open champion Victoria Azarenka 6-3, 6-1 in the resumption of their rain-delayed clash.

Svitolina will now face Elise Mertens in the final eight, after the Belgian beat Aryna Sabalenka 2-6, 7-6 (7/1), 6-0.

Like Konta, Sabalenka faced a double-header on Thursday, and was responsible for the fall of another grand slam champion – 2018 Australian Open winner Caroline Wozniacki.

The unseeded Belarusian saved three match points to beat Wozniacki 5-7, 6-2, 7-6 (7/4) – and looked to be on course to defeat Mertens too, until the No.14 seed launched a decisive surge to clinch a second-set tiebreak and pull ahead in the deciding set.

World No.1 Simona Halep fared better with her double-header, winning both her matches on Thursday and booking her place in the quarter-finals.

The Romanian battled through three gruelling sets and three hours on court to beat Russia's Anastasia Pavlyuchenkova 7-6 (11/9), 4-6, 7-5, but her dismissal of five-time Wimbledon champion Venus Williams was a much quicker affair.

Winning 77 per cent of points on her first serve, Halep claimed a 6-2, 6-2 victory in an hour and 14 minutes.

Her next opponent will be No.6 seed Caroline Garcia, who overcame Maria Sharapova 6-3, 6-2.

Meanwhile, No.8 seed and former Wimbledon winner Petra Kvitova also crashed out of the competition, as Kiki Bertens took a straightforward 6-3, 6-2 win.

Bertens dominated the 2012 Rogers Cup champion from the start, serving strongly and breaking Kvitova five times.

She will now face Australia's Ashleigh Barty, who toppled France's Alize Cornet 7-6 (7/3), 6-4.

Elsewhere, reigning US Open champion Sloane Stephens defeated Carla Suarez Navarro 6-2, 7-5 to set up a quarter-final encounter with Anastasija Sevastova.

The Latvian beat No.10 seed Julia Goerges 6-3, 7-6 (7/2).