Sydney Leroux was a 6-year-old first-grader when Christie Rampone made her debut with the United States women’s soccer national team.

That was 17 years ago and now the two are teammates on the U.S. squad, Leroux an energetic forward and Rampone a wise defender. Each is among the best in the world at her position, so when they go against one another in practice, as they did this month during the national team’s two-week training camp in Carson, the matchups are more challenging than what either will face in most games.

But as important as each player’s talent is to the team’s success, the wide gap in age and experience separating the 38-year-old Rampone from the 23-year-old Leroux is no less valuable, Coach Tom Sermanni says.

“You need a balance,” said Sermanni, who took over the U.S. program in January when Pia Sundhage stepped aside after collecting two Olympic titles and a World Cup silver medal in five years. “Your team is constantly getting rejuvenated. The key is to try to do it as seamlessly as possible.


“So it’s really a process where you, hopefully, continue to have a balance between experienced players and younger players pushing through. It’s important for a team dynamic. It’s important for that energy. And it’s important to create that kind of competition.”

Sermanni, who recently concluded his first December camp ahead of next fall’s qualifying games for the 2015 women’s World Cup in Canada, would seem to have found that balance. In 2013, his unbeaten team used as many players over 30 (five) as it did players under 23.

Veteran players, he says, bring wisdom and experience. Youth brings energy and a new perspective. And no two players demonstrate that better than Rampone, whose 287 appearances are second-most in U.S. history, and Leroux, who made her first start with the national team less than 11 months ago.

This month Rampone and Leroux worked against each other every day during camp, learning from and teaching each other.


“I know her strengths and her weaknesses,” Rampone, the team captain since 2008, said of Leroux. “So if she does something great at practice, I’ll tell her. But [with] her strengths, she’ll still beat me. And then she’ll say something to me.

“It’s constant communication even though, in practice, you want to win at all times.”

Her teammate agrees.

“That’s the beauty of playing on this team,” said Leroux, who scored 10 goals in 15 games this year. “Your practices, those are going to be the best. Because you’re going against players you’re really not going to see that much at the international level.”


It’s that level of competition and her desire to improve that drew Leroux from Canada, where she played on two age-group national teams, to the U.S. at 15.

“I made the decision to play on the best team in the world,” said Leroux, who is battling Alex Morgan, newcomer Christen Press and FIFA world player of the year Abby Wambach for playing time at forward. “You could make the argument that I would be starting for Canada. I don’t want to. I want to be on the best team in the world and I want to fight against the best players in the world to play.

“So that’s what I’m doing right now.”

Rampone, meanwhile, figured by now she’d be trying to control daughters Rylie, 8, and Reece, 3, and not world-class strikers like Leroux. She hinted at retirement during the 2012 London Games, but changed her mind shortly after becoming the first American soccer player to win four Olympic medals.


“I didn’t get that feeling that I was done,” she said. “I thought I would have this overwhelming feeling like ‘That’s it. I’m hanging them up.’ But I didn’t feel it. I didn’t want to just walk away from the game and have regrets. So I figured, ‘Oh, let me give it another shot and see where it goes.’ ”

Where she hopes it goes is to another World Cup, which would make her the first American to appear in five of them. And the years haven’t robbed her of any speed. On most days, she can match Leroux and Morgan, the fastest players on the team, stride for stride, and on her better days she beats them. When she can’t keep up with her legs, she uses her head.

“It comes with experience,” she said. “As you get older you understand the game more. You’ve been in a lot of moments and you learn from your mistakes.”

That longevity has also left Leroux with some daunting goals to aim for. If she’s able to hang on until she’s 38, for example, she might wind up going against Rampone’s eldest daughter who, coincidentally, was a 6-year-old first-grader when Leroux made her national team debut.


“I hope so,” the former UCLA standout said with a smile. “I definitely hope I can do what Christine’s done. It’s awesome.”

kevin.baxter@latimes.com

Twitter: @kbaxter11