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Tom Sermanni needs hardly a second to start ticking off his greatest memories leading the Australia women's national soccer team.

With Sermanni as coach, the Matildas qualified for the 2007 World Cup, won their first World Cup game that year to get to the knockout stage, and in 2010 won the Asian Women's Cup.

"That gave the team that extra belief that they could achieve things. They'd gone from being a competitive team to a team expecting to win games," Sermanni said.

Sermanni left Australia to coach the U.S. women's national team in 2012 and will have to push all that nostalgia aside Sunday when the Americans play Australia in an exhibition at the Alamodome.

"My second favorite team is Australia," Sermanni said. "It will be strange. I was with the team for a long time, and probably 80, if not 90, percent of the players coming out on the field made their first cap with me as national coach."

Sermanni, a Scotland native, transformed Australia from a regional lightweight into a world power that rose as high as No. 9 in the rankings. His job now is to steer the world's most powerful team to another World Cup title in 2015 and keep the U.S. on top of the women's game that has been steadily catching up to the Americans.

The U.S. has won the last two Olympics, but hasn't won a World Cup title since 1999. The Americans lost to Japan in the 2011 final.

Sunday's game is the first of three this month for the U.S. national team and Sermanni already has his eye on 2015 as he sizes up a roster deep with talent.

"It will come around in a heartbeat," he said.

The U.S. is undefeated in its first 12 games under Sermanni with 10 wins and 21-0-2 against Australia in the history of the series. Sermanni's 25-player roster for training camp is a mix of solid veterans like international career goals leader Abby Wambach and goalkeeper Hope Solo and younger players looking for a breakthrough for 2015.

Sermanni said he's not experimenting with tactics, but hopes to evaluate younger players over the next three games. After Sunday, the U.S. plays two matches against New Zealand in San Francisco on Oct. 27 and in Columbus, Ohio on Oct. 30.

"It's hard to judge a player when they come on for 15 minutes when you're already up 3-0. You want to judge players from the start, playing 90 minutes in games that matter," Sermanni said.

"He's still trying to figure out personnel," Wambach said. "He's running out a lot of new players ... You have to prove yourself all over again. That's the kind of thing we all relish. We accept that kind of challenge.

Wambach said Sermanni already has established that he wants the defense to play a higher line to win the ball in the middle-third and attacking-third of the field. By design, that would give Wambach even more opportunities to score.

While evaluating his new players, Sermanni may tempted to watch his former ones who came up through his system in Australia. His last game with his old team was a 6-2 loss to the U.S. in 2012.

"They have very good memories with him. They are all looking forward to seeing him again," Australia coach Hesterine De Reus said. "I think they are proud to play against them and show what he taught them."

But even with those connections the past, Sermanni said the move to the U.S. was a healthy one for both himself and his old squad.

"Eight years as a national coach is a long time. I think it was a good time to renew, for somebody new to change things a little bit," he said.