MIAMI, FL, USA - Some people wait a lifetime for Monica Niculescu's Fed Cup moment, and the Romanian has parlayed her deciding doubles win into a stunning singles success at the Miami Open, scoring her first Top 20 win in just over a year.

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"I’m still thinking about it," a smiling Niculescu said after upsetting former World No.1 Garbiñe Muguruza in three titanic sets on Court Butch Buchholz. "When I want to feel good, I go on YouTube and watch the highlights!" 

Picture it: Ostrava, 2019. Niculescu watched countrywoman Simona Halep level the first round tie against defending champions Czech Republic and two wins apiece. The contest came down to the doubles, and enter the Queen of Craft. 

"When I want to feel good, I go on YouTube and watch the highlights. It was the atmosphere, the result for your country, the fact that it was 2-2 and you’re playing the seven-time champions, the Czechs, in Czech! It was fantastic."

- Monica Niculescu on Romania's Fed Cup triumph

Pairing Irina-Camelia Begu, they took on Barbora Krejcikova and Katerina Siniakova, the 2018 WTA Year-End World No.1 Doubles team.  Rallying from a set down, Niculescu and Begu shocked the dynamic duo to clinch their first World Group semifinal.

She recalls the weekend in a way that allows even the absent to feel the magic of the moment.

"It was the atmosphere, the result for your country, the fact that it was 2-2 and you’re playing the seven-time champions, the Czechs, in Czech! It was fantastic.

"I’m happy but I’m also sad because it’s over. I still want to relive that moment, because it was an amazing feeling. It gave me more trust and confidence in myself. To do that for your country, to beat the Czechs, the defending champions, was amazing. Plus, I played really good in that match, both Irina and I. We’re a very good combination!"

For the 31-year-old with a joy-sparking slice forehand, the milestone permanently closed a chapter of her career she would rather forget, one where a left calf injury derailed her 2018 season.

"It was very tough because it was a serious injury," she explained in the mixed zone following a Friday autograph session. "I’ve had stress fractures, but nothing like this. It didn’t heal, and I didn’t know what to do. I couldn’t make movements on court because of this problem. I would just work on my upper body, and then I would have to go and play, unsure if the injury was even healing, and it was still hurting."

The former World No.28 had played solid tennis at the Miami Open's final Crandon Park installment, reaching the third round with a win over 2017 Wimbledon semifinalist Magdalena Rybarikova - her last Top 20 win before beating Muguruza. Then came the injury, forcing her out of the clay court season. She made tentative steps back to avoid missing Wimbledon, but didn't completely resume her schedule until just before the North American summer hardcourt swing.

All of this was enough to rattle even the typically optimistic veteran. 

"In the end, it was so much time out, and when I came back, it was like I didn't know how to play tennis anymore. It was tough to play in the important moments. I was missing, and I wasn’t feeling the tennis anymore."

Niculescu's face soon brightens, thinking of the success she's since enjoyed.

"Step by step, I started to feel better on court. I usually like Miami, and I played well here last year, where I had a good match against Sloane - even though I lost. I’m feeling good, so hopefully I can keep up my tennis and be healthy. It’s good!"

Winning two matches in qualifying, her win count has doubled in the main draw, with former World No.1 Caroline Wozniacki standing between her and a spot in the Round of 16. Confident in her form, Niculescu hopes to bring a little more Fed Cup magic to Grandstand on Saturday, where she might make another moment to remember.

"There were many Romanians in the crowd, and I had so much support. They were cheering for me after every ball. I like that I moved well, saw the court well, and I could make amazing shots."

Ever-exuding an endearing mix of glee and gratitude, she ends the interview with a flourish.

"I love it here. I like the new stadium, all the facilities we have, so I’m happy we’re here in Miami!"