Edoardo Bove of Roma was struck by a beer bottle hurled by the supporters after his team's defeat to Lazio, their bitter rivals, in a furious Coppa Italia quarterfinal that resulted in three red cards.
Before discarding the bottle, the 22-year-old took a blow to the back and fell to the ground while being replaced.
The lone goal was scored by Mattia Zaccagni.
Gianluca Mancini of Roma was also sent off following the final whistle. Pedro of Lazio and Sardar Azmoun of Roma were both ejected in injury time.
The winner for Zaccagni came from a penalty that the video assistant referee gave for a foul on Valentin Castellanos committed by Dean Huijsen.
In the semifinals, Lazio will either play Frosinone or Juventus.