Meet Mia Hamm — soccer mom.

Once the most prolific scorer in international soccer, Hamm is now guiding one of her twin daughters on the field. Six-year-old Ava enters her second season of fall soccer, with Hamm and husband Nomar Garciaparra on the sidelines.

So is Ava as intense as her two-time World Cup-winning mother and former All-Star shortstop father?

"Sports are all about being social and doing it with your friends at this age," Hamm said. "She's had fun and she's competitive."

Hamm, Julie Foudy and Brandi Chastain visited a soccer camp in Manhattan on Monday and promoted "The '99ers," the latest in the ESPN Films Nine for IX documentary series that will air Tuesday night. Using video footage by producer Foudy, "The '99ers" highlights the behind-the-scenes frivolity and intensity of the 1999 U.S. national soccer team during its successful quest for the World Cup.

The film reunites eight players from the team, including jersey-twirling Chastain, workhorse Michelle Akers and goalie Briana Scurry. The veterans also host a round table with current stars Alex Morgan and Abby Wambach, who recently surpassed Hamm's record of 158 on her way to 160.

It's a short swing before the 41-year-old Hamm returns home to California, where daughter Grace — who likes dance and play softball — and toddler Garrett await. Garciaparra also has been on the East Coast, covering the Little League World Series for ESPN in South Williamsport, Pa.

Here's five things to know about the film, Hamm's take on the latest women's pro soccer league and Chastain's six-pack abs.

LEVITY, PLEASE: Foudy wanted to make the film to show that sports still can be fun, even at the elite level. She watches parents on the sidelines and kids playing with "a seriousness to it that is exhausting and scares me. I hope it's a good reminder for parents that sports are this great gift and we should enjoy them — laughter is permitted."

In 2006, Foudy started a sports leadership academy that hosts soccer camps and focuses on leadership skills. For the film, she gathered her teammates in January to reminisce in an empty Rose Bowl, the site of their World Cup penalty kick shoot-out victory against China before a sellout crowd of some 90,000. An estimated 40 million Americans watched on TV — still the most-watched U.S. soccer match.

RELUCTANT STAR: Hamm epitomized "we vs. me," preferring to deflect praise onto her teammates. She gets emotional in the film describing their bond. Foudy says Hamm refused to take more salary than her teammates during contract negotiations, noting "she was huge in terms of setting this humble mentality that really was the hallmark of our team."

How did the greatest goal-scorer in international soccer — with 158 goals when she retired in 2004 — stay so grounded? Foudy says her response would be "'I'll be the best player in the world when I can run all day like a Kristine Lilly or lead like a Carla Overbeck or head the ball like a Michelle Akers or finish like a Tiffeny Milbrett.' That was Mia, that's what I loved about her. She did it with such a graciousness."

WOMEN'S PRO LEAGUE: Hamm watched a Seattle-Portland game of the National Women's Soccer league this summer, catching up with former teammate and Portland coach Cindy Parlow Cone after the sellout match.

"The crowd was cheering and singing before the first whistle. Just amazing. I was so excited for those players, who maybe weren't at a World Cup or Olympics, who get to play in that environment," Hamm said.

Portland is one of the four teams that clinched a spot in the NWSL playoffs this weekend. She's optimistic the league, partly financed by the U.S., Canada and Mexico soccer federations, will flourish.

"Hopefully, we're talking about more franchises and more players. I think it's important to get some of the top European talent because you want it to be the best league in the world."

PENALTY KICK/SIX PACK: Against China in '99, coach Tony DiCicco chose Chastain for the decisive fifth penalty kick. She agreed to take it left-footed because she was "so exhausted after 120 minutes and in 120-degree heat, all I could get out was 'yes,' and I was thinking 'now go away because I need an ice towel on my head.'"

She never made eye contact with the goalie, ripped the shot into the upper corner, tore off her jersey and twirled it around her head before her teammates mobbed her. The photo of Chastain in shorts and jog bra with impressive six-pack abs made the cover of sports and news magazines.

Does she still have the six pack? "They're in there, not too far from the surface," says Chastain, with a laugh. "That's a big picture to have to keep up with, I try to keep it close."

Husband Jerry Smith coaches the Santa Clara women's soccer team and Chastain said she's "on the field every day with the girls or chasing my 7-year-old (Jaden) around." She's a commentator for the Olympics and World Cup and would "love to cross over to the men's side, since they hire men to do women's soccer. Need to keep pushing the envelope."

PASSING TORCH: Wambach surpassed Hamm for most international goals with a four-goal performance against South Korea on June 20.

"I texted her, I tweeted about it. I think I tweeted every goal," Hamm says, with a laugh. "It's an amazing accomplishment. I don't want her to take it lightly because she's worked so hard."

Hamm says when she played with Wambach in the WUSA, the first women's pro league, she "took a little focus off me and let me run a little bit freer. It brought a little bit more of the love of the game back for me."