A third Celtic fan is recovering after being stabbed in Rome.
The supporter needed hospital treatment after he was attacked in the early hours of Friday morning following Celtic’s victory over Lazio, but it is understood he has since been discharged.
Other Celtic fans reported being attacked after a shuttle bus taking them back from the stadium on Thursday night broke down.
Supporters said they were “ambushed” as they were forced to walk back into the city.
Italian police said 12 Lazio fans have been arrested following disorder during the evening.
It came after two Celtic fans were stabbed by masked attackers outside a pub in Rome on Wednesday evening.
A Celtic spokeswoman said on Friday: “We can confirm that another supporter was injured after being stabbed early this morning in Rome.
“We are currently attempting to make contact with the supporter but understand that he has been discharged from hospital and is expected to make a full recovery within around 10 days.
“We can also confirm that a group of Celtic supporters were also attacked after last night’s match after a bus had broken down.
“Again, the club and British Consulate will aim to give as much support as possible to all supporters requiring assistance.”
James Mervyn, 21, a Celtic fan from Belfast, was on a supporters bus which he said stopped five minutes into the journey.
He said: “Fans could smell burning as soon as we were on the bus and thought Lazio had slashed the tyres, and then we were told to get out by the bus driver and one other guy who looked like police.
“We then walked through a dark road beside the river, everyone screamed ‘Lazio, Lazio’ and we ran.
“I turned round behind me and Lazio fans were there with smoke bombs and knives.
“We then ran for 15 minutes up the road but little to no police presence. Scary experience as children and elderly supporters were on the bus.”
Other fans took to social media to describe how they were attacked as they returned from the stadium on Thursday evening.
Michael McFarlane tweeted a video of fans walking in the dark and wrote: “Our shuttle bus broke down 1km from the stadium. Driver chucked us out, meaning we had to walk through the Lazio neighbourhood.
“After this video, about 20 Lazio fans sprinted from the dark and ambushed the group at the river. Got away safe, not sure about others.”
Rab Robertson wrote: “Fair squad of us ambushed, weans the lot, completely co-ordinated, hopefully all safe,” while Thomas Lunday tweeted: “Not enough buses to take everyone back to the city, so rest of the fans had to walk a couple miles further on, that’s when they where ambushed by casuals.”
The Celtic fan liaison officer had advised supporters to “keep a low profile” as they returned from the game.
He tweeted: “Wee update for fans in Rome, don’t walk back to town, get taxis or shuttle buses back to the city and keep a low profile.”
The club had issued safety advice to fans amid tensions after a match between the clubs in Glasgow last month.
The Glasgow club and Lazio were charged by Uefa over “illicit chants” heard during their Europa League match on October 24.
Celtic were also charged over the display of an “illicit banner” during the game, which they won 2-1.