Five United fans were stabbed before the Champions League encounter in Rome and needed hospital treatment.

"There's little to say," Sensi said. "I am disappointed that incidents have happened again. But this is a common phenomenon in football and does not only involve Roma."

The trouble marked the second time in a row a game between Roma and Manchester United in the Italian capital was marred by violence.

The quarter-final meeting between the two teams in the Italian capital last April left several United fans injured when police baton-charged United fans inside the stadium.