Thousands of Liverpool fans arrived at Stadio Olimpico in Rome for the Champions League semi-final on buses flanked by a large police escort.
Supporters cheered and chanted as they were held in a large queue outside the ground before kick off.
A massive security operation by Italian authorities, assisted by officers from Merseyside Police, saw major landmarks surrounded by a ring of steel and Liverpool fans directed to designated safe areas.
Police with riot shields and batons patted down supporters and Liverpool stewards checked tickets as they boarded the buses in Villa Borghese.
Many AS Roma fans attended the game early to greet their team bus and some set off flares and firecrackers on the opposite side of the stadium to the away entrance.
Authorities said earlier they had had no reports of any issues and many Reds supporters kept a low profile while sightseeing and drinking in the city in the build up.
Liverpool won the first leg 5-2 but the game was overshadowed by the attack on Liverpool fan Sean Cox outside Anfield last week.
The football club and the police warned fans travelling to the game and ex-Roma player Francesco Totti urged calm amid concerns of similar disorder in Wednesday's return leg.
Mr Cox, a 53-year-old father of three suffered serious head injuries after being assaulted outside Anfield stadium on Tuesday.
Two men in their 20s from Rome have been charged with violent disorder over the incident.