Casey Phair was 16 years and 26 days old when she stepped onto the field for South Korea for the first time. It was July 25, 2023, and South Korea was playing its Women's World Cup opener against Colombia.
Phair came off the bench with 12 minutes left in the game in Sydney, Australia, officially making her the youngest player in Women's World Cup history. The distinction piqued the interest of professional clubs globally -- and Phair knew what she needed to do next.
"I played in the World Cup with and against the best players," Phair said in an exclusive interview with ESPN. "Coming back from that, I don't really see how I could play U-17 and then go to college. I wanted to keep getting better and not just peak at the World Cup, then go down and go to college and then have to get back up to a professional level."
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Less than six months after making her international debut on the world's biggest stage at the World Cup, the 16-year-old is taking a big next step in her rapid rise. On Thursday, she was announced as Angel City FC's newest signing, inking a three-year deal with the Los Angeles-based club. She is the latest in a wave of teenagers to sign with the National Women's Soccer League, which continues to adjust its rules to allow teams to acquire talented young players.
Phair spent the weeks after the 2023 tournament testing the waters of professional soccer. She trained with NJ/NY Gotham FC -- close to her home in New Jersey -- and the Kansas City Current in addition to Angel City. Her time in Los Angeles felt the most natural, she said. There, even among players twice her age, Phair was just another player trying to help the team.
"One of the biggest things I liked about L.A. was that it was similar to Korea, where I felt very comfortable in the environment and just meeting the staff and all the coaches and the other players," Phair said. "They were just so welcoming. They gave off the vibe that they wanted me there and that they wanted to help me. I thought Angel City had the best plan for me."
The feeling was mutual. Angela Hucles Mangano, Angel City's general manager, said the team took notice of Phair in her debut at the World Cup. Hucles Mangano was impressed with Phair's poise and maturity at the highest level of soccer. Then she and the team got to see it in person during training. Hucles Mangano said it was an "easy" decision to sign Phair after speaking with Phair and her parents.
"We're excited to have someone that still is in technically a developmental stage, but already has some of these attributes that you're hoping will resonate at that next level," Hucles Mangano said.
From a World Cup debut to the NWSL's young, new world
Less than a year ago, Phair assumed she would take "the normal route" and play in college before turning professional. Her rapid ascent with South Korea's senior team changed that trajectory as she became the first mixed-race player, male or female, to appear in a World Cup for South Korea.
Englishman Colin Bell took over as head coach of South Korea in late 2019 and vowed to modernize the style of the team to help it compete globally. Phair's more aggressive style of play -- a style common to U.S.-developed players -- fits the model Bell seeks.
The 2023 Women's World Cup was a crucial part of that makeover. After a pair of late appearances in the team's first two group games, Phair started and played 86 minutes in the group-deciding match against two-time champion Germany. Before the World Cup, Phair usually played in front of crowds of a hundred fans -- mostly parents -- lining the fields for her youth soccer games. On that day in Australia, nearly 39,000 fans were on hand in Brisbane for the Group H finale -- and South Korea was relying on Phair to lead the forward line.
The game ended in a 1-1 draw, leaving South Korea last in the group and Germany shockingly eliminated. Bell said afterward that it was time to "build a new team" -- and Phair was meant to be the focal point.
"I wanted youth and enthusiasm up front," Bell told reporters. "It was important to show and prove that we have talented players. That energy went through the whole team."
Bell is tough on Phair to keep her grounded, she said. The coach recognizes her potential and has told her as much, but he is as demanding of her as he is the veteran players with vastly more experience. Phair says she prefers direct communication -- it is what she grew accustomed to from some of her early youth coaches.
"They didn't sugarcoat things," Phair said. "That was how I grew up to be the player I am now. I think coaches that are just very up front, I connect with the best. I like when people just tell me the way it is and don't try to be nice."
Angel City head coach Becki Tweed will now navigate that process with Phair. Tweed was in charge when Phair joined Angel City for training in September, and she was hired full-time after guiding the team to the playoffs as interim coach in 2023.
Hucles Mangano said the plan for Phair is individualized, just as it is for every player, something the club takes pride in. Before last week's NWSL college draft, the club staff held two days of meetings about how to continue to strengthen its culture and lay out a vision for the future. That type of work, Hucles Mangano said, creates the welcoming team environment that Phair described as a trialist.
Phair's plan will consist of a balance between expecting results and understanding that production might not come immediately.
"It is definitely about how we can push and apply pressure so that there's an understanding of what it does take to be in this environment at this level to perform, but also understanding that she might have a little bit more leeway in some respects because she isn't there yet," Hucles Mangano said. "So, I think it is that kind of nuanced balance of a push yet being forgiving."
Teenagers in the NWSL are no longer an anomaly. The "normal route" to the professional ranks is changing in the United States, raising questions about the necessity of the draft and the need for better development pipelines.
Last year, the NWSL introduced a new mechanism that allowed teams to sign up to two players under the age of 18, and that allowance will double to four in 2024. Claire Hutton, whom Phair calls a close friend from crossing paths locally at the youth level and from training together at Gotham, just signed with the Kansas City Current via the U-18 entry mechanism.
At Angel City, Phair joins a team already accustomed to young players. Alyssa Thompson, the team's No. 1 draft pick in 2023, started for Angel City and went to the World Cup while still attending high school locally last year. Thompson's younger sister, Gisele, who just turned 18, signed with Angel City last month.
Mangano points to Angel City's intentionality around having multiple teenage players so that they don't feel like they are in silos -- and Phair already feels that impact.
"I think the norm of going to college and then going through the draft is kind of changing now," Phair said. "A lot more younger players are signing professionally. I think that's really good to see like as a woman's player, to see women's soccer develop like that. And the league is getting a lot stronger. So, it's just great to see. My friends are also in the league, so it doesn't put me on an island and I can relate to people."
The road throughout the U.S. and learning to adapt
Phair exudes confidence beyond her years. She describes herself as relatively outgoing and talkative, which is helpful in new, intimidating environments -- and she has plenty of experience navigating those.
Phair was born in South Korea to an American father and a Korean mother, making her eligible to represent either the U.S. or South Korea. Her family moved to the United States a few weeks after she was born, but Korean culture remained a staple in the house, from Phair speaking the language with her mom to writing in Korean before attending American grade school. She went to one U-17 camp with the U.S. women's national team before committing to South Korea.
"It just felt right to me," Phair said about representing South Korea.
The Phair family relocated a few times throughout the U.S. for her dad's job in marketing, each new destination representing a shift in Phair's soccer career as well. She was a center-back in New Hampshire, a central midfielder after she moved to Massachusetts, and a forward in Tennessee, a position she brought to her most recent home, New Jersey.
Phair's game took off in New Jersey at the powerhouse club Players Development Academy (PDA), where she played with older girls before playing with the club's boys' teams. Phair remembers towering above the boys her age in her first season playing alongside them, but a year later she was the shortest player on the field.
"That was one of the key things in my development, was training with the boys," Phair said. "They play so differently than the girls and just little technical things I picked up on from them like my speed of play with them and also using my body, because obviously they're bigger and stronger but then if I use my body one way, I can get past them."
Mike O'Neill, the director of coaching for PDA's girls' programs and the head coach of Rutgers University's women's soccer team, has worked with Phair for the past three years. What sets her apart, he said, is not just being well-rounded but her ability to adapt to the constant change she has experienced.
"When you get into an environment, it's being able to adapt, being able to adjust, and to be able to do that quickly," O'Neill said. "Because sometimes what happens is if it takes you too long, they don't think that you can handle that level. But I think what she has is she has this ability to get into an environment, kind of assess the environment, and then she's off and running."
Hucles Mangano said the ability to have Phair join the team environment was crucial -- and still rare. There, Angel City saw how she interacted with her would-be teammates, taking their advice but playfully dishing out rebuttals to their jokes.
"I think that was just really the critical piece," Hucles Mangano said. "We still have not gotten to the stage where we're seeing in person all of our players that we bring in. That is our next level before we sign them. We've seen them either on video or we've seen some players if we've played against them within the league. But for her specifically, that's why training was so important because that's probably -- without putting her in an actual game -- the best way to actually see [her skills]."
Manchester City forward Erling Haaland and retired Swedish forward Zlatan Ibrahimović are two of Phair's biggest influences as a No. 9. Phair watches YouTube videos of Haaland to study his positioning and how he uses his strength on the ball. She likes to watch Manchester City midfielder Kevin De Bruyne, too, for his "magic on the ball," even though he plays a different position. (Ironically, she supports Manchester United.)
The player who first inspired Phair to thrive as a forward, however, will be an opponent in the NWSL: Mallory Swanson. Weeks before Swanson's 19th birthday, the U.S. women's national team and Chicago Red Stars forward ultimately skipped college to turn professional in 2017.
"She was one of my biggest influences growing up and I idolized her a little bit," Phair said of Swanson. "To play in the same league as her now just feels so full circle but also so mind-blowing to me that at such a young age I can do that."
Angel City signed Phair as a striker, but her adaptability could lead to other opportunities. The key in everything will be balance, Hucles Mangano said -- balancing the need for Phair to produce with her ongoing development, and not pigeonholing her into a single type of player.
"I think what is great about where she is in [this] stage of her career is that she might start in one way and, based on the needs of the team and the ability that she does have, be able to play maybe in a couple of different positions," Hucles Mangano said.
"We brought her in to develop as a No. 9 -- that is how we are looking at her. However, right now, we're still looking at who we'll be using in that No. 10 role, and what does that look like? So, I think that is part of when I say, allowing some room for growth, but also her ability to develop over time."
Calling Angel City home
Virtual schooling was already part of Phair's life because of the travel demands created by playing for South Korea. She has traveled there every month since the World Cup for camps and competitions, which has allowed her to see her mom's side of the family more frequently.
For now, Phair said the plan is for her mom and dad to rotate time with her in the L.A. area before the entire family -- her two younger brothers also play for PDA -- moves there at the beginning of the next school year.
Playing in the NWSL will allow Phair's family to be close to her throughout the process, a decision she made intentionally. She already spends enough time on the road playing for South Korea, she said.
In a couple of months, Phair will have her first opportunity to experience an Angel City game in a game-day environment that sets the standard in the NWSL. A rescheduled match meant that Phair did not get to attend a home game at BMO Stadium during her time training with the team. She has mostly experienced the sellout crowds in a very Gen Z way: through Instagram reels.
Her first experience will come with a view from the field, looking up at the stands filled nearly to capacity, her parents likely among the nearly 22,000 fans. There will be external pressure and expectations that she and those close to her will need to temper. She is 16, after all, and she will need time and patience to adjust to the professional level.
Phair's view of what lies ahead is a window into her maturity, the type of humility that can set her apart from her peers. From her early days in New Hampshire to the World Cup, Phair is a team-first player. It shows when she talks about things like the hat trick she scored against Thailand in October in Olympic qualifying. Phair doesn't even mention it in conversation about the training camp because she is disappointed that South Korea did not ultimately qualify for the Olympics.
That is the attitude that Angel City hopes will pay dividends for the player and the club in the near future.
"I just want to help the team as best as I can," Phair said. "I know everyone on the team wants to win the NWSL championship, so I just do whatever it takes, whatever I can give to the team to help us reach that goal. And then also develop as a player, but just from a team perspective, to really win a lot of games, hopefully the championship and just contribute what I can to the team."