USA midfielder Savannah DeMelo is "stable and alert" after collapsing on the pitch while playing for Racing Louisville in the National Women's Soccer League.

The incident occurred in first-half stoppage time during Louisville's match at Seattle Reign on Sunday.

DeMelo, 27, received treatment on the field before being taken to hospital in an ambulance.

Both teams confirmed the match, which was goalless, will be resumed at a later date.

"Savannah is stable and alert and getting the attention she needs," the NWSL posted on X.

"Our first priority is her health and safety. We are in close communication with Racing Louisville's medical team.

"The NWSL remains committed to ensuring that the highest standards of medical care and emergency response are in place at every match."

DeMelo also had to be withdrawn from a match against Bay FC in March because of health issues.

In May, DeMelo, who has won seven caps with USA, announced she had been diagnosed with Graves' disease and hyperthyroidism.

"Sending all our love to Savannah DeMelo and everyone at Racing Lou FC," Seattle Reign posted on X.

"We stand side by side with Louisville during this time and thank our fans for their support."