The 23-cap Matildas goalkeeper joins from Norwegian club Arna Bjornar, after two highly successful W-League spells at Perth Glory and Brisbane Roar.

During her time in Australia, 25-year-old Arnold rose through the ranks to become one of Australia's premier goalkeepers, competing with Lydia Williams for the Matildas' number one spot.

She won the W-League Goalkeeper of the Year award at just 20-years-old, winning it twice more in 2014 and 2018.

At the Red Stars she will serve as backup to experienced U.S national team goalkeeper Alyssa Naeher, who is a long-serving Chicago keeper with 53 caps for the Stars and Stripes.