NEW YORK, NY, USA - At 15 years old, American wildcard Coco Gauff is clearly enjoying her first US Open, exciting the home fans with a dramatic win over fellow teenager Anastasia Potapova.

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As Gauff was kicking off her comeback from a set down on Louis Armstrong Stadium, 26-year-old Timea Babos was finishing up a quieter win on Court 4, but for a player who had to fight for her eighth appearance in the main draw, it was a debut all its own.

"I feel great!" she trilled to those who gathered around the small interview cubicle after advancing over No.28 seed Carla Suárez Navarro. "Honestly! I’m not going to lie. Things are going back in place, and I’m happy for that. I’m a different person again and I really enjoy being out there. I have a great attitude, no matter who I play, and it’s been going on for a couple weeks now. I’m happy with how I’m playing and hopefully it can continue like that."

The hard-hitting Hungarian took her thudding serve and ground game, one that helped earn quality qualifying wins over Kurumi Nara, Lara Arruabarrena, and Varvara Lepchenko - all former Top 60 players - into the main draw with immediate success as former World No.6 Suárez Navarro retired after the opening set. The win is just her third at a major tournament since the 2017 US Open, and books her a second round clash with Gauff.

"She’s a big, new, young star, and so it’s going to be a great match. It’s going to be a great opportunity, a big stage, and a big court, which I love. This is what we play for, so it’s definitely going to be an exciting one."

Babos has long told a tale of two careers. The best individual doubles player of her generation, she has qualified for the WTA Finals for the last four years, with three different partners, and won the last two titles with Andrea Sestini Hlavackova and current partner, childhood friend Kristina Mladenovic.

A former WTA doubles No.1, her singles ranking was an unimpressive World No.148 just three months ago. The same week she hit that seven-year low, Babos picked up the phone and called esteemed WTA coach, Michael Joyce.

"I’ve known her personally for a while," he explained on Sunday. Babos had just qualified for the US Open main draw, all but ensuring a return to the Top 100 after less than 12 weeks together. "She played doubles with Jessica Pegula years ago. I always thought she was a great player, hard worker. I was excited to try and help her out."

Noted for his work with Pegula and a near-decade long partnership with five-time major champion Maria Sharapova, Joyce had recently split with 2014 Wimbledon runner-up Eugenie Bouchard and initially agreed to a trial run following the French Open, which she and Mladenovic won for their second major title in 16 months.

"She’s a great doubles player, so she can probably do that on her own, because it’s naturally really good for her. In singles, she hasn’t had a coach in a while, and has been struggling a little bit. I’ve been happy to help her."

"In singles, it’s just you out there. You have your coach and your team on the side encouraging you, but it's a matter of being able to accept that you need to get better at that stuff. You can give good advice, encourage and work them hard because you’re right there with them. Timea knows when she starts to get negative or down on herself. It’s that self-belief where, I think a good coach can help the players believe better."

- Michael Joyce

Babos has long been a double threat, peaking at No.25 in singles and regularly challenging the game's best in thrilling, three-set matches - though her 1-21 record against the Top 10 would indicate a struggle when it came to securing the actual upsets.

"She’s a very smart girl. She knows her game, her strengths and weaknesses. I’ve worked with other players who, I don’t want to say they don’t know their game, but they turn to you to make every decision for them. Timea has traveled by herself, started really young, comes from a tennis family – her dad was a player and a coach – so she knows the game incredibly well.

"But sometimes when you’re like that, you can start overthinking things. It’s funny because in doubles, she’s very positive and confident. She feels like she’s one of the best in that discipline. In singles, it’s been easier to get lost a bit, and when you have different people and coaches giving you advice, sometimes it can be a bit overwhelming, and you forget your basics.

"She’s gone through a lot of the same stuff I went through. I gave her examples of how I handled situations and how other players I’ve worked with have handled them. I felt like it was perfect, ultimate teamwork."

It's the kind of teamwork Joyce had been looking for after promising partnerships with Bouchard and British No.1 Johanna Konta - during which she shocked Serena Williams at the 2018 Mubadala Silicon Valley Cassic - both came to premature ends.

"I was with Maria for seven years and Jessie for five or six, and I always prided myself on being one of those coaches who didn’t jump around. I actually always used to talk about how I was lucky, because I believe that, for a coach to do a good job, you really have to know the player. For anyone, you might have some ideas on what you want them to do, but every player is different: when you approach them, how you give them information, how they handle wins, losses, or expectations.

"It takes a long time to know somebody, and we’re kind of in a moment right now where coaches and players are changing a lot. I really don’t like that as a coach, and as a player, it’s silly that they do that."

"There are tons of great coaches out there, but it’s not easy to connect with someone and really find the right energy. The whole team gives me great atmosphere and a lot of positive energy every day. I think you can learn every day and use that experience to be better. I feel looser, but I don’t like the word, ‘confidence’ because it’s something that’s really hard to define or describe. I’m just happy with how I’m playing and performing."

- Timea Babos

Joyce could relate in that way to Babos, who herself had spent almost five years with Thomas Drouet, and, even more importantly, in her willingness to rebuild her ranking on the ITF Pro Circuit.

"I have a tremendous amount of respect for her. She won the French Open and then the next day, she got to the Challenger event in Manchester before I did. She’s put a huge effort into bringing her singles back and to me, that’s incredibly impressive. A lot of players would think about how they just made $400,000 and ‘I don’t need to play that Challenger.’ That made me excited right off the bat."

Narrowly missing out on a Wimbledon wildcard by finishing runner-up at the $100K event in Ilkley, Babos shook off a Roehampton qualifying defeat to 2013 finalist Sabine Lisicki to show steady improvements throughout the summer, reaching the semifinals of another Pro Circuit event in Vancouver a week before the US Open.

"I could tell she was disappointed at Wimbledon. She asked me if I wanted to go home to my family because she could play doubles on her own. Instead, we went indoors for five or six days, worked a lot on certain things, and it gave us a good training block to get ready for this summer. She’s been physically working hard with a good trainer and physio, and things are really starting to pay off."

From Pegula to Bouchard - and now Babos - Joyce is no stranger to the art of the comeback, and seems to have turned art into stone cold science.

"The first goal is to get them to where they can get into main draws, because when you're Top 70 or 80, it’s easier to make a schedule and plan training. With the sacrifices Timea makes, she could go home or take weeks off. She showed me that, from Day 1, she wanted to get her singles ranking back to at least where she’s in main draws of tournaments again, and she was willing to pretty much to anything to do that. As a coach, you can’t ask for much more."

For now, neither can Babos, who enthusiastically reminded me she has few points to defend between now and the Australian Open next year, a scenario that can potentially springboard her even further back up the WTA rankings.

"We’re not setting high goals at the moment," she clarified on Tuesday. "I’m just going step by step and it’s working really well. I’m not saying where I want to be; I’m just going out to every match, trying to do my best. It’s more important to go slower, but go further than just to have one shot up, which I’ve had a couple times before, and would then have a more difficult time. Every day is a new opportunity and new challenge, and I really believe in this; I really believe in the work. Even if something doesn’t work out, I can always say I did everything I could in the best way I could." 

Joyce is even more optimistic, if not confident - Babos bumps on the concept of confidence, theorizing, "it’s something that’s really hard to define or describe - of his star student's future prospects.

"I have no doubt that she can get higher than she ever was. She’s a great player, and little things in her game are already improving. She’s winning a lot of matches. When I work with a player, I don’t just work with anybody. I work with players I feel can do good, and that I’m a good fit for them. Hopefully, some of my confidence – and I feel like I sometimes have more confidence in the player than they do in themselves – rubs off on them.

"I think Timea is capable of doing great things in singles. I still think she has tons of things to improve on, but she’s already a great player. I feel like that confidence I have in them rubs off sometimes, which goes a long way."

Babos will draw from that well of support against Gauff, who will likely have a stadium behind her, but fresh off a trip to the Frozen musical, a cold reception - to borrow a phrase - might not bother her anyway.