British number one Johanna Konta eased into the quarter-finals of the Miami Open with a 7-5 6-1 victory over Lara Arruabarrena.
Konta was given a testing time in the opening set by the Spaniard, who had won only one match this year prior to the tournament.
But 10th seed Konta's serving was key and she broke Arruabarrena at 6-5 up before going on to dominate.
Konta will now play third seed Simona Halep in the last eight.
Romanian Halep saved a match point before beating Australian Sam Stosur 4-6 7-5 6-2.
"I felt I played myself more into the match a bit more," said Konta, who is into the quarter-finals in Miami for the second successive year.