British number one Johanna Konta moved into the Miami Open fourth round with a dominant win over Elise Mertens.

Defending champion Konta, ranked 14th in the world, secured a 6-2 6-1 victory over the Belgian world number 21 in 65 minutes.

The 11th seed could next face 37-year-old Venus Williams, the world number eight.

American Williams plays 26-year-old Dutchwoman Kiki Bertens, ranked 29th in the world, later on Friday.

Konta was helped in the first set by Mertens registering six double faults – including four in one game – and she played an almost perfect match as she swept into the last 16.

“I tried to take my game to her and managed to do that for big pockets of time, but it’s never easy to come through so I’m really happy,” Konta said.

“I definitely have a great relationship with this tournament, the biggest title of my career has come here. Hopefully I can get to the end again.”

• Live scores, schedule and results