MONCALIERI, Italy — Daisy Osakue grabbed her pink sneakers from the terrace and packed them in a suitcase embossed with the Italian flag. All around her family’s apartment, newspaper articles, old photos and posters hailed her success in track and field. Dozens of medals hung from pictures of her family celebrating in traditional Nigerian dress.

“Just need to get my medicine,” she said on Thursday morning, her left eye tearing and bloodshot, as she grabbed prescription drugs and eye patches. They sat on a coffee table next to white flowers a neighbor had dropped off in solidarity.

Before this week, Ms. Osakue, 22, had a modicum of renown for throwing the discus farther than any other Italian woman ever in her age group.

But since Sunday, when young men outside her apartment complex threw an egg that cut her cornea, she has become the bandaged face of Italy’s explosive debate over whether the country is becoming more racist under its new populist, anti-immigrant government or whether politically motivated liberals and a sensationalist media are unfairly sounding the alarm. What is clear is that Italy is on edge.