British star Harriet Dart breaks down in tears on court before stunning Katie Boulter at Wimbledon

British tennis star Harriet Dart broke down in tears when she thought she was about to get knocked out of Wimbledon by fellow Brit Katie Boulter.

The second-round clash on Centre Court was an absolute thriller, with both women refusing to give each other an inch during the epic encounter.

British No.1 Boulter claimed the first set of the match 6-4, before the impressive Dart, the British No.2, produced a fantastic second set to claim it 6-1.

READ MORE: Novak Djokovic's staggering net worth, high-flying wife and marriage split rumours

READ MORE: Katie Boulter's superstar boyfriend, huge net worth and dramatic on-court incident

The third set was back-and-forth, with nothing to separate the two Brits throughout. Only a tie-break would separate them and decide who would go through.

And Boulter raced ahead in the tie-break, with Dart getting visibly angry when the British No.1 took it to 5-2. Then, when Boulter won the next point to make it 6-2, therefore needing only one more point to win, Dart had to take herself to the back of the court to compose herself.

But what followed was a display of sheer tenacity and grit from Dart, who lifted herself up to produce some magnificent tennis, while capitalising on a number of her opponent's errors, to win 10-8 and advance through to the third round.

The London-born 27-year-old said after the match: "I knew it was going to be a really tough battle. We only played a few weeks ago and it didn't go my way. I wear my emotions on my sleeve.

"I am so happy to be able to get through. Thank you so much for the support it was so fab.

"My head-to-head is absolutely woeful against [Boulter], so I just wanted to try my best out there, even though I was down in that tie-break, I just thought, 'Give it everything you've got, no regrets'.

"It's massive. I haven't played on Court One since I played mixed doubles here a few years ago. So to get my first big win in a big stadium court, in front of a home crowd, it's absolutely surreal."

Dart will play Wang Xinyu in the third round, with the Chinese player having knocked out Jessica Pegula in her second-round match.