Like continents drifting across Earth, change may appear to come slowly to the US women’s soccer team, but when it happens, it happens with a mighty wave of tremors.

Why competition for places is so fierce on the US women's national team Read more

Coach Jill Ellis named her 18-player roster for the Olympics on Tuesday, selecting just seven players from the 2012 Olympic squad. Four players bound for Rio didn’t play in last year’s Women’s World Cup.

That’s not typical for the US team. The most turbulent four-year cycle for the team was 2004-2008, when several players from the 1999 World Cup championship team retired, the team self-destructed at the 2007 World Cup, Pia Sundhage came in as coach, and Abby Wambach and Cat Whitehill were injured. Still, nine players from the 2004 roster were named to the 2008 squad.

To an extent, Ellis’s hand was forced. Since the US women won the World Cup last summer, Wambach, Shannon Boxx, Lori Chalupny and Lauren Holiday retired. Christie Rampone has not returned to the national team. Sydney Leroux and Amy Rodriguez are either pregnant or recently gave birth. Even with the smaller roster size for the Olympics (18 players, compared to 23 for the World Cup), some turnover was guaranteed.

Some of the choices were obvious. Crystal Dunn shredded NWSL defenses after she was omitted from the World Cup roster last year, and though her scoring form has dipped for the Washington Spirit this season, she continues to torment defenses and score goals in international play.

Other choices were anything but obvious a few months or a year ago:

Lindsey Horan: A unanimous pundits’ pick in the weeks leading up to the roster selection but still an unknown quantity a year ago. She had played neither in the NWSL or the NCAA, skipping college to turn pro with Paris Saint-Germain, and she was known mostly as a forward.

Ellis called her in for the Victory Tour series of post-World Cup exhibitions, bringing her in for her first caps since 2013. She settled quickly into a central midfield role, showing off her hard-nosed but creative play for the national team and the Portland Thorns.

Mallory Pugh: The high school senior got her first cap and first goal on 23 January against Ireland. She has only scored once since then but has been a game-changing attacker with composure beyond her years.

“She doesn’t get rattled,” Ellis said in a Tuesday conference call with reporters. “In January, she didn’t know anyone. Now, she’s just one of the players on the team.”

Allie Long: The 28-year-old veteran of WPS, European and NWSL play got 178 minutes of playing time in four national team games in 2014. Then none in 2015. Then none in January, February or March. On 6 April, she got a start against Colombia and scored her first and only two national team goals in a 7-0 rout. Solid performances in two June friendlies against Japan were enough to claim a roster spot. Her bio page at USSoccer.com is blank.

Megan Rapinoe: The winger has been a vital player for the US women in the last three major tournaments, starting with a sensational cross to Abby Wambach to save the USA from elimination in the 2011 World Cup quarter-finals. The bad news: she tore her right anterior cruciate ligament in December on the team’s ill-fated trip to Hawaii, and she hasn’t seen game action since then.

Ellis said Rapinoe hasn’t steered clear of contact in training, and the team’s plan will be to build up her fitness as the tournament progresses.

“She does have an ‘it’ factor – what she can give us on set pieces and crosses,” Ellis said. “She’s one of the best crossers in the world.”

Heather O’Reilly (alternate): All this turnover on the team, and there’s still no room in the first 18 for a three-time gold medalist midfielder renowned for her work rate. She’ll only play if others are injured.

“We just added more depth to that position,” Ellis said, citing Pugh, Dunn, the in-form Tobin Heath, versatile forward Christen Press and Rapinoe as players who can attack on the wings. “I think it’s the hardest position to make on our team.”

Aside from recent injuries to Rapinoe and Carli Lloyd, this team has no apparent sign of weakness. The troubling signs leading up to the World Cup last year – the stagnant offense, the reliance on older and slower players – aren’t there. This team comes into the Olympics as the clear favorite.

When Ellis was asked whether she felt less pressure and more job security during Tuesday’s media conference call, her laughter interrupted the question. But she did sign a long-term contract extension last year, and she says her decisions have been made with the long term in mind.

“Building for the future was certainly something that came into play when it came to the initial players I brought into the pool,” Ellis said. “If I was going to bring new people in, they would be people who had a shot at the 2019 (World Cup) roster.”

Not that this year will be taken for granted. Ellis said she interrogated every player to make sure they were still hungry and focused after last year’s World Cup triumph.

Now she’s excited about the mix of returning veterans and the youngsters who could form a core of this team for the next decade, let alone the next World Cup/Olympic cycle.

“You had players at the end of their careers in the last World Cup,” Ellis said. “But I think this group is hungry to make their mark as a new team.”

USA squad

Goalkeepers: Alyssa Naeher (Chicago Red Stars), Hope Solo (Seattle Reign FC)

Defence: Whitney Engen (Boston Breakers), Julie Johnston (Chicago Red Stars), Meghan Klingenberg (Portland Thorns FC), Ali Krieger (Washington Spirit), Kelley O’Hara (Sky Blue FC), Becky Sauerbrunn (FC Kansas City)

Midfield: Morgan Brian (Houston Dash), Tobin Heath (Portland Thorns FC), Lindsey Horan (Portland Thorns FC), Carli Lloyd (Houston Dash), Allie Long (Portland Thorns FC), Megan Rapinoe (Seattle Reign FC)

Attack: Crystal Dunn (Washington Spirit), Alex Morgan (Orlando Pride), Christen Press (Chicago Red Stars), Mallory Pugh (Real Colorado)