Described as "one of the most important players" on the US national team over the past decade by team-mate Alex Morgan, the 31-year-old retires with 123 caps for her country.

But it is not a decision Ertz, twice named US player of the year, says she has taken because she no longer believes she can compete at the highest level.

Instead, the midfielder has chosen to finish on her own terms, revealing her priorities have changed since becoming a mother in August 2022.

"It's not because mama can't play, mama can play," said Ertz, a key figure in the USA's successive World Cup triumphs in 2015 and 2019.

"She has just adapted her priorities and I think that just comes with age.

"I'm proud of my growth and I'm grateful that soccer allowed that.

"But I'm really excited for my next chapter and I'm grateful to have found something I love even more - and that's being a mum."

Ertz received an emotional send-off in a 3-0 friendly win over South Africa in Cincinnati and said afterwards the occasion had given her "closure".

She embraced her team-mates and waved goodbye to the crowd with a smile on her face as she was substituted off to a standing ovation in the 35th minute.

Returning to the pitch to thank the supporters after the match, she ended her speech by dropping the mic and wiped a tear from her eye.

"To any young girl out there who dreams to be here, it's worth it. Every part of it," she said.

Ertz, who is married to NFL player Zach Ertz of the Arizona Cardinals, took a break to give birth to her son, Madden, after the US won Olympic bronze in 2021.

She made a surprise return to the US squad in April and played every minute as a centre-back at last month's World Cup in New Zealand and Australia, where the defending champions lost to Sweden on penalties in the last 16.

In all, the USA lost only 2.8% (three matches) of the 106 games Ertz started in her career - the lowest losing percentage of any player with 100 or more starts in the team's history.

"It's been an absolute joy of a career," said Ertz, who spent the majority of her club career at Chicago Red Stars before returning at Angel City FC in 2023.

"The saying 'it has been a dream come true' is not something a lot of people get to say. But, for me, it has."

She added: "Sport takes sacrifice. I think time with my family is just irreplaceable, especially [considering the age] Madden is.

"Soccer embodies everything I am. I'm going to miss competing at this level. The banter and jokes, sharing the love of the game with those around you, and probably the joy of scoring a near-post header."