Miami Open Masters 2019: Venus Williams, John Isner Advance in Early Sunday Play

Simona Halep survived a scare against Polona Hercog on her way to the fourth round at the 2019 Miami Open Masters on Sunday, coming back to win in three sets.

Yulia Putintseva did the same as she upset No. 11 seed Anastasija Sevastova, having only narrowly avoided a bagel in the opening set.

In the men's draw, John Isner overcame Albert Ramos-Vinolas, while Kyle Edmund eased past Milos Raonic.

Novak Djokovic, Sloane Stephens and Karolina Pliskova will also be in action.

Here's a look at some of the day's early results:

Men's Singles

(7) John Isner bt. Albert Ramos-Vinolas, 7-5, 7-6 (6)

(17) Nikoloz Basilashvili bt. Robin Haase, 7-6 (3), 6-3

(19) Kyle Edmund bt. (12) Milos Raonic, 6-4, 6-4

(22) Roberto Bautista Agut bt. (15) Fabio Fognini, 6-4, 6-4

Women's Singles

(2) Simona Halep bt. Polona Hercog, 5-7, 7-6 (1), 6-2

Yulia Putintseva bt. (11) Anastasija Sevastova, 1-6, 6-2, 6-3

Venus Williams bt. (14) Daria Kasatkina, 6-3, 6-1

Yafan Wang bt. (25) Danielle Collins, 7-5, 6-1

Full results can be found at the competition's official website.

Halep eventually triumphed on Sunday, but she had to do it the hard way after Hercog took the first set, having capitalised on several poor forehand efforts from the Romanian.

The Slovenian showed some impressive resilience to break back in the second immediately after going behind, too, but she had no answer for Halep when it came to the tiebreaker.

The No. 2 seed quickly raced to a 5-0 lead on the way to claiming the second set:

Halep stepped her game up a gear in the decider, too:

Hercog's resistance soon crumbled, and she'll feel it was a missed opportunity having been within a tiebreaker of the fourth round.

Halep will play Venus Williams, who dropped just four games in her win over Daria Kasatkina, in the last 16.

Meanwhile, Edmund recorded an impressive win against Raonic without having to face a break point.

The pair's only previous meeting came in Florida two years ago, with the Canadian coming back to win in three sets.

There would be no such comeback on this occasion, though, with Raonic hampered by a back problem.

Edmund took to social media to celebrate:

His win set up a tie with Isner. Like Raonic, the American is known for his powerful service game.

"Isner is a similar matchup in that you have to try to get his serve back," Edmund said, per BBC Sport. "It's more just how heavy his serve is and how tough it is to read. I have nothing to lose and have to give my best. I'm feeling good."

Men's No. 7 seed Isner served up 16 aces as he dispatched Ramos-Vinolas in straight sets.