Toure suffered a stress fracture in his right foot while on international duty with the Olyroos in the recent AFC under-23 championships.

The 19-year-old will visit surgeons in coming days to discuss treatment and will be sidelined an "indefinite period", United said in a statement on Wednesday.

Toure has broken the second metatarsal - a long bone in his right foot which connects the ankle to toes - an injury which may take from six weeks to several months to heal.

The injury stalls the meteoric rise of Toure, whose Olyroos' performances were his first internationals.

Toure, who was born in West Africa's Guinea, migrated to Australia with his Liberian-born parents when he was a four-year-old.

Liberia's coach Peter Butler contacted Adelaide United about a potential release of Toure during last November's FIFA international window.

But the goal-scoring attacker elected to pursue an international career with Australia.

Toure's international future was a hot topic after his stunning emergence in Adelaide's successful FFA Cup campaign, capped by winning the Mark Viduka medal for best-afield in the final.

Toure made his Adelaide debut in the tournament's opening round in August and scored five goals as the Reds' retained the cup.

He also scored on his A-League debut last October against Sydney FC - one of two goals in his nine A-League games this season.

Australian Associated Press