Tennis is a sport in which mental strength can make or break a player. For some, losing can turn into a perpetual habit, especially given the isolating nature of the sport. Those who can keep their emotions in check while they are all alone on the court, no matter the situation, are the ones who find the most success.

When Karla Popovic walked off the court in Tempe, Arizona, on Nov. 15, 2015, having just received a beatdown in the last match of her disastrous fall season, one can only imagine the devastation most players would feel in her position. The fourth-seeded Karla had just suffered a quick exit in the second round of the ASU Thunderbird Invitational, relegating herself to the consolation bracket. With the opportunity to end her season with a win, Karla instead was run off the court by ASU’s own Kassidy Jump, who was unseeded.

After a fall preseason that had started with extremely high expectations, the Croatian national found herself at rock bottom in the midst of her sophomore season. Despite having a preseason ranking of No. 64, Karla was feeling the full effects of a sophomore slump, taking loss after loss and being shown the door very early at important competitions.

“When I was very young, I would be upset after losing a match, and I would cry,” Karla says. “But as you grow, you see that it’s just one match in your career, and as long as you give your best, you have nothing to regret after that.”

Karla could have had all the talent and physical strength in the world, but it was her steely mentality that would ensure a reversal of the results from fall. When Karla went back to the drawing board in the spring, she had only her mental strength. It was enough.

Karla hails from the small town of Zabok, Croatia, which has a population of less than 10,000. Karla grew up in an environment where she was surrounded by sports — her parents both played basketball, and her mother additionally ran track.

“When I was very young, I would be upset after losing a match, and I would cry. But as you grow, you see that it’s just one match in your career, and as long as you give your best, you have nothing to regret after that.” -Karla Popovic

After experimenting with a variety of games, Karla fell in love with tennis the first moment she picked up a racket as an 8-year-old — late by Croatian standards.

“Tennis was the first individual sport I tried, and that was something that was definitely better,” Popovic says. “You have more responsibility, and there are a lot of things you can do, and you can explore yourself through the game.”

Although Karla had chosen to pursue tennis, she did not originally train with the same level of intensity as many of the other players at her age. She practiced only three to four times a week with her parents, who would drive her 40 minutes to the Croatian capital of Zagreb to coach her at the tennis courts.

It was only when she reached her teenage years that Karla decided to enter the competitive scene. Her practices became a daily routine, and she ramped up conditioning sessions with her mother, who utilized her track experience to train her daughter.

During these practice sessions, Karla’s parents — her most important mentors and role models — instilled in her the values she still follows today.

“As I was growing up, I had to learn how to stay calm and how to not show any negative emotions but keep positive body language,” Karla says. “That’s always a lesson you have to learn, especially for young kids playing tennis. Always be a fighter and never give up. … Be a hard worker, and be determined.”

One of the worst mistakes a tennis player can make is to second-guess what shot to hit as the ball approaches. When Karla plays, it is evident that she embraces the opportunity to think and act for herself. Taking each ball quickly and on the rise, she leaves her opponents flat-footed, waiting for the optimal chance to take a calculated risk to finish the point with a winner.

Popovic classifies herself as a fighter and acknowledges that the best way to get over a loss is to see it as just one match that should not be taken too seriously. She knows that other players frequently suffer from various failures, but the ones who can continue to rebound no matter how many times they have fallen are the ones who eventually emerge victorious.

“If I put any pressure on myself, it can backfire and block me from what I want,” Karla says. “There was never any pressure from the team or the coaches, but I wanted to prove to myself that I could be here. It was a positive thing that kept me going and working hard.”

According to Karla’s roommate Mia Croonquist, a junior on the Cal women’s crew team, Karla’s discipline and intense focus are her most admirable traits, and once she locks onto one task, she does not stop until she completes it.

Last summer, after a spring season that saw her improve from her dismal fall, Karla committed to taking her game to new heights. She didn’t just want to return to the level of her freshman play — she was ready to jump up the ITA rankings. Not for one second has she taken her eye off the ball.

This laser-like focus is infectious to those around Karla, and she uses this energy and passion to become a leader for the people closest to her. With her confidence at an all-time high, she has grown to embrace this role, especially as she prepares for the responsibilities of becoming one of only two seniors on the team next season.

“Karla brings everything she has to everything she does, and I think it’s coming together for her this season,” says Olivia Hauger, Karla’s doubles partner. “She has definitely risen as a leader, and it shows that when you put in the amount of hard work that she does, you can have a lot of success.”

Karla is still as hungry as ever to achieve a higher level of play — not just individually, but with her teammates, whom she thinks of as her sisters. She remembers the bitter loss her team suffered against Oklahoma State in the semifinals of the NCAA Tournament last spring, and given her new role as a leader, she will look to inspire her team to push through to the final round this year. On the individual side, Karla is still fighting her way to the top of the ITA poll. The nation’s best players await her, and she awaits them.

The rematch.

Flash forward to 2017, and Karla is now ranked ninth in the nation, the highest she has ever ranked in the polls. In a year, Karla has become a dual threat on the court by evolving into a talented and intelligent doubles player — currently ranked No. 23 in the nation with her partner, Hauger.

“I think that Karla set these goals for herself at the end of last season after she had a really good finish to the year that we really wanted to build on,” says Cal head coach Amanda Augustus. “We’re all about players getting better, and (Karla) is a fabulous example of dedication, hard work and commitment.”

After shaking off the woes of her sophomore season and revamping her game mentally, physically and technically, Karla finally had her chance at sweet revenge.

It was the final of the Cal Fall Nike Invitational, and on the other side of the net stood Kassidy Jump once again.

Jump carried herself with confidence, knowing that she had easily beaten Karla before and had every intent of beating her again. But there was no way that the much-improved Bear was going to lose another match to this opponent, especially not in a final — in front of her teammates and supporters at home.

It was as if each ball Karla hit was a controlled release of the frustrations that built up in the previous season. The weight of each shot pushed Jump several feet behind the baseline, opening up the court for Karla to rip a ferocious winner down the line. Karla sealed the deal, 6-1, 6-2, in just about an hour.

It always comes back to that fighting spirit and intense determination. These two traits can do a world of wonder for anyone desperate to get positive results after a stretch of trending down.

If you looked at Karla on the court during her underwhelming sophomore fall and compared her to her emergence as the next star in a long line of great Cal women’s tennis players, there would be no difference in her body language. A fighter fights no matter the result of the last bout, and Karla has shown where that mentality can get you.

Nikhil Bhumralkar covers rugby. Contact him at [email protected].