Johanna Konta knows she has a tough task in front of her as she aims to make the Miami Open semi-finals.

The British number one matched her 2016 run to the quarter-finals by beating Spaniard Lara Arruabarrena 7-5, 6-1 in a tricky fourth-round contest in Florida.

That set up a last-eight meeting with third seed Simona Halep, who saved a match point to beat Sam Stosur in three sets.

Although the Romanian has struggled with injury and form so far in 2017, Konta, typically, is not looking too far ahead.

"I'm happy that I'm still here and get to play another match," she said in her post-match press conference before she found out the identity of her opponent. "I don't necessary believe in open fields because every single player in this draw is world class. So every match is as tough as the next.

"I'm just happy to be still part of the event, and whoever I play next I know it'll be a tough game and I look forward to being a part of it."

A much more difficult night looked on the cards for the 10th seed as Arruabarrena, who had only won one match this year prior to arriving in Miami, played superbly in the opening set and only some impressive serving from Konta kept her in it.

And at 6-5 she raised her return game as well, breaking Arruabarrena to take the opener. She timed it nicely as it was the first time she had been ahead in a service game of the Spaniard's.

The second set was a different story, as Konta began to flex her muscles and hit her opponent off the court on her way to a 4-0 lead.

Konta came through the fourth round match in straight sets (Getty)

A slight mishap saw Arruabarrena break to avoid a bagel, but Konta shut down any hopes of a comeback by seeing out the second set and the match.

On her performance, Konta added: "I felt I played myself more into the match a bit more. As the match went on, I felt clearer and clearer on how I wanted to play and what I wanted to do out there from my perspective.

"I'm quite happy I was able to execute that reasonably well. And also make it tough for her to stay in that match with the level that she was playing at."

Arruabarrena only won one game in the second set as Konta surged ahead (Getty)

The top three seeds all made it through to the quarter-finals of the Miami Open.

Angelique Kerber barely broke sweat as she dropped just four games in a 6-2, 6-2 win over qualifier Risa Ozaki, while second seed Karolina Pliskova did not have to work much harder to get past her fellow Czech Barbora Strycova as she came out a 6-1, 6-4 winner.

The same cannot be said for third seed Halep, who saved a match point before eventually coming back to beat 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.

However, fourth seed Dominika Cibulkova was ousted as she fell in straight sets to Lucie Safarova, with the Czech, who specialises in doubles, winning 7-5 (7/5), 6-1.

Sixth seed Gabrine Muguruza is also out as illness caused her to retire during her clash with Caroline Wozniacki, with the Dane having just won the first set.

Seventh seed Svetlana Kuznetsova was another top 10 seed to fall as she was soundly beaten by Venus Williams, with the veteran claiming a 6-3, 7-6 (7/4) success.