ROME, Italy -- No one has ever known what it's like to be thrust into the world's spotlight after winning the US Open as a teenage qualifier. But 2019 US Open champion Bianca Andreescu certainly knows what it's like to try and back up a career-making title run while your body refuses to cooperate. 

Andreescu and Emma Raducanu's much-anticipated first-round match-up at the Internazionali BNL d'Italia ended abruptly on Tuesday evening, when Raducanu was forced to retire down 6-2, 2-1 with a lower back injury she has been nursing for weeks. Raducanu had hoped that a few days of rest after her third-round exit in Madrid would allow the injury to heal itself, but found herself limited during training in Rome.

"I never really knew how bad it was until I kind of went out there," Raducanu told reporters after the match. "I'm still learning when it's right to push my body and push through it, and when's not.

"I guess that's something I'm kind of learning at these tournaments. The difference is I'm probably doing it at bigger tournaments, not smaller tournaments on the way up."

Andreescu could empathize. After winning her first WTA title at Indian Wells in 2019 at 19 years old, she was ruled out of most of the clay season and the entirety of the grass season with a shoulder injury. Her returned and ultimately won Toronto and the US Open, but her season came to an end after tearing her meniscus at the WTA Finals. She did not take the court again for 15 months. 

"I think that you really have to experience it to really know what you need," Andreescu told reporters. "But you're playing the best players. You really have to have the right nutrition, the right game plan, like physically, mentally, emotionally, everything.

"It's not easy being on tour. From January to end of October, that's a long time. You really have to schedule your training properly, your competition, all of that. You also have to know that injuries are a part of the game. But the best thing you can do is try to prevent. I think that's kind of the advice I can give her."

Raducanu's priority now is to prepare herself for her Roland Garros debut in two weeks. She's showed good quality in her first WTA clay season, posting a run to the Stuttgart quarterfinals and Round of 16 in Madrid. Her performances have proven that the surface can be a successful one for her. If only her body would cooperate. 

"I think the last few weeks have been really positive," Raducanu said. "I've learned a lot about myself and my game has definitely improved on this surface.

"But for sure I need to make sure my back is fully right, however long that takes. I need to just keep on it. I don't want to play my next match with a feeling of limitation because I think that I learned my lesson from this week, when to push, and when not to push. Probably today wasn't right."

"I feel like I'm the type of player that always wants to go. Maybe just like her. I would love to play every week."

- Bianca Andreescu

Andreescu said her experience over the past three years has taught her it's OK to step back. 

"I feel like now I know myself and my body more and more, so I'm able to make that decision for myself," Andreescu said. "But I do have an amazing team, as well, that's very experienced and has been in the sport for a long time, so they also help me. I feel like I'm the type of player that always wants to go. Maybe just like her. I would love to play every week.

"When they do see me like that, they also help me. They'll tell me to chill. I'll take maybe a day off, two days off. Even after the two days off, I play even better than maybe if I played those two days."

There's no reason to panic for Raducanu. Still in the midst of her first full season on the Hologic WTA Tour, the 19-year-old is simply going through growing pains. Full training sessions, playing back-to-back days, week after week will take its toll. There is no cheating when it comes to fitness. It simply takes time and hard work to build up the physicality that can withstand the unrelenting competition of the tour. 

"It's weird, because when I'm playing in practice, I can practice for a good few hours a day," Raducanu said. "But the quality of the ball I'm receiving in practice, it's not the same when I'm playing these matches because I definitely feel like the matches are taking a lot more out of me than they probably should.

"I had a match in Stuttgart, my first round, it was, 6-1, 6-2. The next day I felt like I was in bits," she said, laughing.

As for Andreescu, she is enjoying her progress on the court. She played her first tournament in seven months in Stuttgart and pushed Aryna Sabalenka to three sets. In Madrid, she played a near-perfect match to defeat Australian Open finalist Danielle Collins. And though the match ended in retirement, she was extremely pleased with her attitude and performance against Raducanu. 

"I'm very happy with everything," Andreescu said. "Basically I feel like I'm very committed, I'm very determined on what I want to do and how I want to do things now.

"Actually playing my match against Pegula [in Madrid], it was super up and down, but that was a great reality check from the universe. I'm very pleased with how I regrouped from that. Last year I would have cried in my pillow for two days straight. Now I just feel more hungry and motivated to continue and to be better."

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