Alongside Martina Hingis, the tennis star became a doubles champion, picking up several Grand Slam titles.

As her fame grew, Kournikova made millions through brand deals and public appearances.

Curious to learn more about this tennis icon?

Anna Kournikova smiling

Here are a few things you likely never knew about Anna Kournikova.

Kournikova’s mother, Alla, was a 400-meter runner in her youth.

Sergei fostered his daughter’s enthusiasm for playing sports at a young age.

Young Anna Kournikova playing tennis

As she explained, I played two times a week from age five.

It was a children’s program.

According toCNN, Bollettieri’s only thought upon seeing her play was “holy mackerel.”

Anna Kournikova speaking

Moving to the U.S. would later pay dividends in her tennis career.

At age 14,Kournikova wonthe European Championships and the Italian Open junior tournaments.

Kournikova debuted at her first Grand Slam, the U.S. Open, at age 15.

Anna Kournikova on the court

After winning her first-round match against Czech-born Ludmila Richterova, Kournikova spoke positively about the experience.

“It’s already a good tournament for me,” she toldThe New York Times.

“I qualified and then I won my first match.

Anna Kournikova at Wimbledon

So I think that’s great.”

1 seed Steffi Graf.

Despite this disappointment, Kournikova was reflective and philosophical about the experience.

Martina Hingis and Anna Kournikova

I’m sure I’ll learn something from this match," she told theIndependent.

“I’ve had a great tournament; I’m really happy with the way I played.

It’s unbelievable I got to the semifinals.

Anna Kournikova posing by K-Swiss

I was dreaming about this.”

1 seeds Lindsay Davenport and Natasha Zvereva.

Kournikova commented on this blossoming partnership by saying, It feels great.

Anna Kournikova in Escape video

This consistency resulted in Kournikova climbing to the No.

1 ranking in doubles, which was her finishing position that season.

This was remarked upon by tennis journalist Ben Rothenberg.

Anna Kournikova in 2003

Today,Celebrity Net Worthestimates her total net worth at $50 million.

12 on the U.K. and U.S. charts, respectively.

The love affair did not stop there: After the video was filmed, Iglesias and Kournikova began dating.

Anna Kournikova playing tennis

In recent years, Kournikova has mostly kept a low profile away from the spotlight.

It was the back injury that ultimately forced Kournikova to retire.

As she retold the experience toPeople, I never planned or thought that was going to be it.

Anna Kournikova at an event

My back really forced me to stop.

It got so bad I couldn’t tie my shoes, literally.

I would be in excruciating pain.

Anna Kournikova speaking

In a blog post, she wrote enthusiastically about the experience.

I just love playing with all of them; we have so much fun on the court together!"

“In the end, John and I were able to pull it out and win the match!

Anna Kournikova smiling

The children she met in Guam made a thought-provoking impression.

This would be Kournikova’s first competitive match since her retirement at the end of 2003.

The pair faced and defeated Anne Hobbs and Sam Smith on June 29, 2010 (viaThe Telegraph).

Anna Kournikova posing

After the match, Kournikova spoke toThe Guardianabout the challenges that female professional tennis players face.

“It’s a full-time job, it’s 24/7.

You’re week-in, week-out, on the road for 10, 11 months of the year.

You have no personal life.

You have no home life.

It’s not glamorous at all.

After this initial guest appearance, Kournikova joined the program as a regular the next season.

Unfortunately for Kournikova, this opportunity only lasted one season.

“I enjoyed my time on ‘The Biggest Loser’ ranch.

Grand Slam singles champion Svetlana Kuznetsova holds Kournikova in high regard.

“Everyone after her was just after her.

For me, she was a big, huge push.”

She even dismissed Kournikova’s critics who cite her career as a failure.

“Everybody was saying she never won a tournament, hee hee ha ha,” Kuznetsova went on.

“I always defend her when they say ‘Oh, she never won a tournament.’

She was a top 10 player.

It’s not just about winning tournaments.

I think she was great.”