Emma Raducanu has vowed to come back stronger.
CNN  — 

Emma Raducanu says she’ll “come back stronger” after her fairytale maiden run at Wimbledon ended on Monday evening after she retired from her fourth-round match with “breathing difficulties.”

The 18-year-old Brit – who was playing in her first ever grand slam – lost the first set and was trailing 0-3 in the second against Ajla Tomljanovic when she called on a trainer.

During the second set, she frequently bent over with her hand to her stomach, showing signs of discomfort. A first trainer was followed by a second shortly after, with one appearing to listen to her breathing as she sat on Court One.

Having left the court for further treatment, it was announced minutes later that Raducanu would not be returning. Wimbledon later confirmed she had withdrawn from her match.

Raducanu’s popularity has soared this week and she took to social media to assure her new fans that everything was fine.

“I wanted to let everyone know that I am feeling much better this morning,” she wrote on Twitter Tuesday.

“First up, I want to congratulate Ajla on an incredible performance and I’m sorry our match ended the way it did. I was playing the best tennis of my life in front of an amazing crowd this week and I think the whole experience caught up with me.

She said she began to “breathe heavily and felt dizzy” after a number of “super intense rallies” before the medical team advised her to stop playing.

“Although it felt like the hardest thing in the world not to be able to finish my Wimbledon on court, I was not well enough to carry on. I want to thank the people who have cheered me on every single match, I wanted to win so badly for you!

“I also want to thank the All England Club, my team, the LTA, my parents and friends. Last night will go a long way to helping me learn what it takes to perform at the top.

“I will cherish everything we have achieved together this week and come back stronger! Can’t wait to see what’s next on my journey.”

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Raducanu goes off court for a medical time out against  Tomljanovic.

After progressing to her first career grand slam quarterfinal where she’ll face compatriot Ashleigh Barty, Tomljanovic admitted she felt “sorry” for Raducanu.

“I’m actually really shocked,” 28-year-old Tomljanovic said. “It’s obviously bitter-sweet.

“Emma must be really hurt if she came to the decision to retire. To play as a Brit at home is unbelievable, so I’m really sorry for her. I wish we could have finished it. It’s sport, it happens. I’m really wishing her all the best.”

Wimbledon posted their appreciation of Raducanu’s debut run in a statement on Tuesday.

“We were very sad to see Emma forced to withdraw from her match last night and wish her all the best with her recovery. She should be commended for the poise and maturity she has shown throughout the Wimbledon Fortnight and we very much look forward to welcoming her back to Wimbledon next year and in the years to come.”

The end of the road

It was a disappointing end to a remarkable breakthrough competition for the young British player, who was ranked No. 338 before the start of the tournament.

Raducanu beat two top-50 opponents, Marketa Vondrousova and Sorana Cirstea, on her way to the last 16 and became a true fan favorite not just with her tennis abilities, but also with her acts of humility after she was seen cleaning up her own trash after her second round victory.

Raducanu and Tomljanovic were forced to wait until late into the evening to begin their fourth-round meeting due to a five-set thriller between Alex Zverev and Felix Auger-Aliassime before them.

The 75% capacity crowd was clearly in Raducanu’s corner, cheering every point she won like a match winner.

However, after failing to convert some early break points, world No. 75 Tomljanovic showed her experience, claiming the first set under the Court One roof.

She was firmly in control of the second set when Raducanu retired, and the possibility of facing her fellow Australian in the next round has got Tomljanovic excited.

“Because of the circumstances, it hasn’t sunk in that I’m in the quarters,” she said. “But to be playing Ash, two Aussies, with one of us sure to go to the semis – it’s great. I think everyone back home is really happy. I’m thrilled to play Ash. It will be a great match.”

Tomljanovic plays a forehand against Raducanu.

Easing through

Eight-time Wimbledon champion Roger Federer progressed to the quarterfinals of the grand slam on Monday for the 18th time, extending his own record at the competition.

The Swiss looked relatively comfortable on his way to beating 23rd seed Lorenzo Sonego 7-5 6-4 6-2 on Centre Court in the fourth round, extending his lead at the top of the all-time list for most Wimbledon quarterfinal appearances, ahead of Jimmy Connors.

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Federer celebrates winning match point against Sonego.

“I’m extremely happy,” Federer said. “Again, tricky conditions – inside and outside – against Lorenzo who is always dangerous, but I felt that after that first set, I was able to control things. It was a great match and I couldn’t be more excited to be in the quarterfinals. It’s a big moment and I’m very, very happy.”