Some sporting rivalries run deeper than a match won or lost. They run in the blood.

So it is with Katie Boulter and Harriet Dart whose simmering tensions on the tennis court flows from a proud lineage in the game established by their mothers.

Mothers, who faced off against each other for supremacy in their generation of tennis. 

Sue Boulter introduced her daughter to tennis aged just four, having been inducted to the sport by her own mother Jill when was still a young girl in Leicestershire. 

While Susie Dart took her daughter along to her first practice session aged seven at the Cumberland Lawn Tennis Club, in Hampstead, north London, after her own successful career. 

The mothers were both county captains for Leicestershire and Middlesex and would have faced each other at tournaments organised by the Lawn Tennis Association.

Born just four days apart, their daughters were destined for greatness and ultimately to clash. 

When the youngest of the Dart and Boulter broods faced off at Wimbledon yesterday the competitiveness took on a sharper edge than just pure raw adrenaline. 

The will to win in Dart’s face was clear with the tears which ran down her cheeks, as it looked in the opening exchanges her rival Boulter was again going to beat her.

But now both 27, the delight on Dart’s face was unmissible when she claimed only her second victory against Boulter as she clasped her face in her hands beaming.

Before their latest clash Boulter claimed victory in six of their seven of their previous encounters. 

The last one being at Nottingham, when Dart so frustrated by an umpire’s decision going agains her offered a £50,000 bet that the ball was out not in. 

She shouted to the umpire: ‘I promise you,’ she continued, ‘if you watch it back, I will bet £50,000 that ball was out. Honestly. I would shake your hand right now.’ 

The first time the pair encountered each other was also in Nottingham when during her celebration her 6-3, 7-5, victory Boulter jabbed at her own head. 

Dart sure this to be an effort at mind-games having won the contest and told Boulter it was unnecessary. 

The pair clashed as they met at the net before turning to the umpire with Boulter saying it was nothing personal. 

But the tension between the two refuses to go away. 

In the build up to the clash, Boulter said: ‘Playing a Brit in the UK on the grass is never an easy draw and I’m expecting an absolute battle,’ Boulter said on Monday.

‘I do have to draw on the last things that I have played with her and use that to my advantage in the next round. I think it’s going to be extremely tough. I have a lot of respect for her on this surface. It’s one of her favorite ones.’

‘This is actually her home club. She’s been here since she was a tiny tot with her mum.’

And after her loss a visibly emotional Boulter spoke to the press. 

She wish Dart the best of luck, saying: ‘We’ve been through this long journey together. I wish her the very best. I hope she goes far in this tournament.’

Asked if she felt Dart’s tears were distracting she added: ‘I mean, I don’t know. I actually didn’t notice. I try not to look too much.’

Dart was also asked about her emotions during the match during a press conference just after the game finished. 

She said: ‘I let things kind of get to me a little bit. I managed to regroup, which was the main thing, just fight my hardest. 

‘I was really pleased, as you probably saw at the end, to get away with the win.’ 

Dart tried to play down rumours of the bitter rivalry when she was directly challenged about it after her win. 

‘Gosh, rivalry? My record is absolutely woeful against her. I wouldn’t really call it a rivalry. We grew up together. I think we’re only a couple days apart. 

‘It’s a tough sport that we play. I mean, she’s been having an amazing year, not just this year but last year as well. 

‘So to be able to beat her here shows how much I’ve come forward as well within my game. I mean, she’s an amazing player.

‘Honestly, I wasn’t really expecting to win today because, as I said, my head-to-head with her is absolutely awful. To finally get a win is nice.’

And if their rivalry on the tennis courts was not enough- the two support rival football teams. 

Boulter is a keen Leicester City fan and actually likens herself to a fox, the nickame for her club. 

‘I see myself as a fox. They’re fighters, they keep going.

‘I think I’ve been through a lot of adversity on and off the court, and them on the pitch as well.’

While Dart is a die-hard Arsenal fan and frequently uploads pictures of herself at the ground in the team’s red and white colours. 

Leicester famously beat Arsenal to the Premier League title when they defied odds of 5000 -1 to triumph in a remarkable season in 2016.