Sermanni has ended his second stint at the helm of the Australia women's team to become head coach for the world's No.1 side
Tom Sermanni has brought his eight-year stint as Matildas head coach to an end, quitting the post to take over the USA's women's national team.
Having led the Australia to the quarter-finals at the past two women's World Cups, as well as winning the Asian Cup in 2010, Sermanni has made a huge difference to the Matildas since taking over as head coach in 2005 - his second stint in the role.
Sermanni believes the Matildas are in a good position to build into the future but said it was the right time for him to take on a new challenge.
"From a personal perspective, this was definitely not an easy decision to make and, in the end, it became quite an emotional one for me," Sermanni said.
"In football, and in life, it's all about timing, and with Australian women's football quite settled at the moment with the national teams and the Westfield W-League, the timing of this challenge to coach the number one women's football team in the world was at the right time for me to accept.
"There is plenty of great talent coming through the Australian women's football system and in the coming years I am confident that Australia will be a world force.
"But eight years is a long time for any coach to be in a position and now seems to be a good time to bring in some new ideas and energy into the Matildas set-up."
Sermanni has been a central figure to the growth of the Matildas over the past two decades.
The 58-year-old Scot coached the Matildas from 1994 to 1996 before re-joining the team in 2005, leading them to the final of the Asian Cup in 2006.
But the opportunity to coach the best women's team in the world was not something Sermanni could ignore and Football Federation Australia CEO Ben Buckley accepted the decision.
"When Tom tendered his resignation our immediate reaction was sadness that he would no longer be coaching the Matildas but we understand the motivation behind his decision and wish him all the best for his new challenge ahead with the US women's national team," Buckley said.
"Tom's legacy for women's football in Australia will be felt for many years to come as he has helped transform our women's national team to a very professional and competitive group of players."