Johanna Konta through to the Miami Open quarter-finals after defeating Lara Arruabarrena

Johanna Konta set up a Miami Open quarter-final with third seed Simona Halep after easing to a 7-5, 6-1 victory over Spaniard Lara Arruabarrena.

The British No1 had a tough time in the first set, and only some superb serving kept her in it.

Konta raised her returning game at 6-5 to take the opener and pressed her advantage in the second, racing into a 4-0 lead.

Arruabarrena fought back to break serve but Konta broke again and served out the win.

Konta, seeded 10, has reached the last eight for the second successive year. She said: “As the match went on, I felt clearer and clearer on how I wanted to play and what I wanted to do out there. I’m quite happy I was able to execute that and make it tough for her to stay in the match, with the level she was playing.”

Halep had to save a match point before coming back to beat Sam Stosur 4-6, 7-5, 6-2.

The Romanian was staring down the barrel at a set and 5-2 down before she reeled off 11 of the next 13 games to book her last-eight spot.

In the men’s event in Miami, Roger Federer continued his fine form with a 6-4, 6-4 win over Juan Martin del Potro.

Federer, 35, the Australian Open and Indian Wells champion, has lost just once this year after missing much of 2016 with injury.