The Italians can be seen throwning punches at police at High Street Kensington.
The mob were eventually pushed back to Earls Court before kick-off.
The match ended in a thrilling 3-3 draw.
Roma fans clashing with Police in London before their game at Chelsea tonight. (Via @PintsandPyro) pic.twitter.com/sU5cVShUES
— The Away Fans (@theawayfans) October 18, 2017