Cori Gauff is not ready for her remarkable Wimbledon journey to end just yet as she fought off two match points to beat Polona Hercog and move into the fourth round.

The 15-year-old has been the story of the Championships so far, having come through qualifiers to beat Venus Williams in the first round, but it looked like it was coming to an end with Hercog on the brink of a straight-sets victory.

But Gauff climbed off the canvas and showed she has a strong fighting spirit to add to her precocious talent, earning a 3-6 7-6 (7) 7-5 victory over the Slovenian.

Ukrainian Svitolina made hard work of it against Greek Maria Sakkari, eventually winning 6-3 6-7 (1) 6-2 on the seventh match point.

Victoria Azarenka called the warning she received in her straight-sets defeat to Simona Halep as "pathetic".

Azarenka received the sanction after bouncing her racket in the first set of her 6-3 6-1 loss on Centre Court.

It is little surprise the Belarussian was frustrated as she was in the midst of a capitulation that saw her lose 11 of 12 games, having been 3-1 up in the first set.

"I think it was pathetic, to be honest," she said.

"I understand the no tolerance, whatever it was, two metres outside of the court. I didn't damage the court and anything like that.

"It's like you have to be with no single emotion on the court, and that's just not tennis. I'm sorry, but it's not."

Halep described the win in the battle of the former world number ones as her best performance of 2019.

"I'm very satisfied," she said. "I think this was my best match this year. I played really well. I felt actually very confident."

Karolina Muchova defeated 20th seed Anett Kontaveit and Petra Martic won in three sets over Danielle Collins.