By James Toney at Wimbledon

The biggest question at this year's Wimbledon ... where is the sun? The answer is out on Centre Court, also going by the name of Lulu.

In a championship that is seemingly being played in perpetual stygian gloom, 23-year-old New Zealander Lulu Sun is a much-needed beaming ray of light.

Emma Raducanu knows all about sporting fairytales, following her own improbable run through qualifying to win the US Open three years ago.

While this fourth round defeat - especially with the draw ahead so open - will sting, there was plenty of respect for the unknown qualifier who ended her, and Britain's, singles ambitions at the All England Club this year.

Sun, 23, is playing in just her second Grand Slam tournament and had never beaten a player outside the top 100 before this week, China's Zheng Qinwen, the world number eight, her first round victim.

Her 6-2 5-7 6-2 win makes tennis history in New Zealand - a quarter-final appearance wiping Māori legend Dame Ruia Morrison, who made it through to the fourth round of Wimbledon in 1959, from the record books.

"I've beaten two top ten players in the last two weeks and that's a big deal that I'm going to take real confidence from," said Raducanu, determined to accentuate some positives.

"Six months ago I'd have signed on for the fourth round of Wimbledon but the defeat makes me more hungry, especially as I feel I'm finally tracking in the right direction.

"Her tennis was just better and she deserved the win. She was very aggressive and she took the ball on every chance she had. I expected a tough match, she just kept swinging and never really missing.

"I need to work on the consistency of being good every day, this just makes me more determined to do that. All I want to do is improve my tennis, that fire is back."

There were plenty of similarities in the back stories of these players, both fiercely intelligent, trilingual and forged from a kaleidoscope of nations and influences.

Sun was born in New Zealand to a Chinese mother and Croatian father, and was raised in Switzerland from the age of five. Raducanu was born in Canada, also to a Chinese mother, and a Romanian father, and moved to Britain as a toddler.

Sun, the world number 123, is actually ranked 12 places higher than her rival, whose position has slipped after so long off the court through the injuries that followed her Flushing Meadows heroics.

However, any fear she'd freeze on the Centre Court stage were soon dispelled as Raducanu struggled with her range and rhythm and the Kiwi took instant advantage. If the girl born in a town with 'more sheep than people' was bothered by a partisan 15,000 crowd, it didn't show. There was no awe, only shock.

"I obviously had to fight tooth and nail to beat her as she's going to run for every ball. I don't even have the words now," said Sun, who will play unseeded Croatian Donna Vekic in the last eight.

She was a joy to watch, full throttle at every shot, the quality of her returns and the precision of her volleys, leaving an increasingly frustrated Raducanu on the back foot.

Time after time, after the Brit had dug out a stinging return, she saw it fizz back past her with interest, Sun's tactics of swinging hard at every opportunity paying spectacular dividends.

Raducanu had arrived at the All England Club managing expectations, insisting she'd be happy just to win one match.

An appearance in the fourth round eclipses that target but she will privately view this as a missed chance, with the late night defeat of number two seed Coco Gauff, by fellow American Emma Navarro, she'd have been the only Slam champion in the bottom half of the day.

Her decision to withdraw from her mixed doubles match with Andy Murray - denying him one last Wimbledon game - continues to divide opinion, though quite why is a puzzle. After all her injury problems, it's frankly bizarre to question why she wouldn't focus her attention on the singles. Sentiment rarely pays the bills in sport.

Judy Murray stirred it up dubbing Raducanu's withdrawal 'astonishing' before promptly sending her social media accounts private as the debate she fuelled raged. She was back online a few hours later claiming she was being sarcastic, make of that what you will.

"I don't think it was a mistake to accept the chance to play with Andy, I had to prioritise my singles and I stand by it," added Raducanu.

"It was a tough decision because playing with Andy was a dream. I didn't want to take his last match away from him.

"With every decision people are entitled to their opinions, there was a cloud around it but I don't think I'd have done it any other way, especially with my history of injuries. I'd hadn't seen what Judy Murray said, I'm sure she didn't mean it.

"Hopefully he'll play in the Olympics and get another farewell then."

Elsewhere, Italian Jasmine Paolini continues to enjoy her best season and booked her quarter-final appearance when American 12th seed Madison Keys tearfully withdrew when serving for the match.

"I'm so sorry for her, to end the match like this is bad," said Paolini. "What can I say? I think we played a really good match."

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