Mia Hamm Praises Natalie Portman and Jennifer Garner for Their 'Tremendous' Support of Angel City FC

Mia Hamm thinks the future of women's sports is in good hands.

As one of the many celebrity investors in Angel City Football Club, Hamm, 51, tells PEOPLE that the female-led and founded soccer team is lucky to have A-Listers like Natalie Portman and Jennifer Garner as owners.

"I think having them involved just takes our game and our club to a different level and connects us with a group of people that we weren't able to," Hamm says.

Portman, 41, and Garner, 50, "have been tremendous," says Hamm, who especially appreciates the actors for "sharing their voices and their platforms, but also their energy getting behind it the way they have."

On Sunday, Angel City Football Club celebrated its second home opener in Los Angeles, where Portman and Garner joined 22,000 fans to cheer on the popular team at BMO Stadium.

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Hamm says "it means so much" to her to see how women's soccer has evolved since the club was founded.

"I mean, being the mom of two girls, just for them to see their heroes playing every single day and not just in the game of soccer, but I think having access and the opportunity to follow someone from their sport," says Hamm, who shares twin daughters Ava Caroline and Grace Isabella with her husband Nomar Garciaparra.

"I have a daughter that plays lacrosse, so being able to do that, watching college games on TV or on your phone, I think just seeing people that look like them and have the same interest I think is really important for their confidence and their growth and development."

But Hamm points out that there's still a discrepancy between salaries for male and female athletes.

"We're still trying to get our salaries to a position where these women are compensated similarly to men's players. I know we have a lot more work to do and the wonderful thing is everyone is so committed to doing that, both front office, our supporters and definitely the players."

And Hamm is proud that Angel City fans connect over more than just their love of the sport, adding that the team's supporters "have been tremendous" since the team was founded.