We start the third set and Harriet Dart ramps up the pressure with back-to-back aces to move to 40-15.

But a Katie Boulter winner and then a Dart double fault takes us to deuce.

Harriet Dart returns a serve long and we go to a decider.

It's been a very odd set of tennis. Boulter has played her normal game, while Dart has let several calls get to her. British number one Boulter must be the favourite from here.

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Forehand winner from Boulter. 40-30. Set point.

Harriet Dart drops to her knees after a Katie Boulter ace. She's again not happy with the call and looks at the line judge.

30-30.

We do have a tennis match going on, with Katie Boulter now serving for the second set.

Right then, the tournament referee has come over to Harriet Dart. This is what I've been able to hear her say on the microphones at the side of the court:

"We've had some bad calls, also she [the umpire] told me there's no chalk.

"I said a call was embarrassing I'm not sure how you can get a code violation from that.

"Ninety-five percent I'm right on Hawkeye, you should check my record."

Much better from Dart who wins the next three points to go up 40-30.

She then wins a fourth in a row with a cross-court backhand on the run which Boulter can only return into the net.

Harriet Dart hits two errors. 0-30. Katie Boulter is two points away from the second set.

Harriet Dart is still playing some great tennis though, and recovers to 30-30.

But Katie Boulter then goes up another gear, holding to 30 to move to within a game of the second set.

It's very telling just how warmly Katie Boulter's winners are currently being received. The crowd seemed far more neutral in the first set.

They are fully behind the British number one now who hits a fine forehand into the corner. 30-0.

A fourth game point in a row for Harriet Dart and she does finally get the hold as Katie Boulter slices wide.

Dart's still unhappy at the change of ends and says to the umpire: "I would bet £50,000 that ball was out. Honestly it's a joke. The whole crowd said out. Chalk dust. You know I'm right."

She also asks for the match referee, who will come at the next change of ends.

Harriet Dart now argues with the line judge after a first serve is called out.

She manages to set up game point but it's saved by a Katie Boulter winner. That's cheered warmly by the crowd.

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Dart saves the break again and then has yet more words.

The umpire says her complaining must stop now, otherwise she'll get a code.

Dart manages to save the break point, but Boulter sets up another with a winner at the net.

This is not a good look at all. Katie Boulter sets up break point but all Harriet Dart wants to focus on is that call.

She put a tennis ball behind the baseline to show where she believed Boulter's shot landed.

Harriet Dart is still furious with the umpire who calls a Katie Boulter shot in.

"How!" screams Dart and then she turns to the umpire and says, "This is embarrassing, you're embarrassing yourself."

The crowd aren't impressed, and neither is the umpire. "Watch yourself Harriet." 30-30.

Harriet Dart really isn't happy with Katie Boulter's ace being called in, she's just had a word with the umpire.

Boulters takes the first point of Dart's latest service game with a brutal forehand return.

Katie Boulter could do with a comfortable hold to keep the pressure up.

She charges to 40-0, has a minor wobble - double-faulting for 40-30, but then holds with an ace.

The two-game cushion is back.

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This is a big hold of serve for Harriet Dart!

She sets up game point after Katie Boulter hits a forehand wide, and then sneaks over the line with a backhand that snookers the approaching Boulter, right at her feet, causing the British number one to net.

Dart saves the break once more after a Boulter backhand goes long.