Two young soccer fans are recovering from severe burns after being hit by flares at Melbourne's Federation Square during the Socceroos' match with Argentina.

Samuel Rogan was watching the clash on Sunday morning when a flare hit his friend's face and then ricocheted, hitting his arm.

The 19-year-old said his "skin was bubbling" after the flare was set off when Australia scored a goal.

READ MORE: Family's heartbreak over fatal stabbing of teen at St Kilda beach

"It felt like someone was just sitting there with a fire torch just on my arm," he told 9News.

"(My mate) is now burnt under the eyelid and lost his eyelashes, and his skin on the wrist is all third-degree burns."

The pair were rushed to the Alfred Hospital and are facing weeks of pain.

"He could have lost his eye," Rogan said.

"I could have lost half the skin on my arm.

"It could have been a lot worse."

Flares have been seen across the world at various sites set up for people to watch their country in the World Cup.

On Sunday morning there were so many flares set off that the screen at Federation Square was not visible. 

About 15,000 soccer fans gathered at Federation Square in Melbourne on Sunday morning.

Rogan warned of the dangers flares pose.

READ MORE: Students, carers getting biggest welfare boost in decades

He said he would not likely return to a similar gathering again.

"When you start throwing stuff, and fireworks, that's when it gets out of hand, and it's just not appropriate, he said.

"I don't think I see myself at Fed Square, rather just watch in my lounge room at home."

The Socceroos were defeated by Argentina 2-1 in the World Cup round of 16 match.