Daniel Fulham was detained in Bulgaria following the Hoops’ European tie with Ludogorets.
However, a source has told sundayworld that, “due to all media attention we now believe Daniel is flying home tonight.
“Fair play to all media for the support and attention he got,” the source added.
Another source told independent.ie that the Department of Foreign Affairs here have confirmed his identity to Bulgarian authorities and have secured his release.
Officials are now helping him leave the country and get home.
Shamrock Rovers had earlier issued a statement in support of Fulham who they described as a “long-standing club member”.
"A Shamrock Rovers fan was held by Bulgarian border police when he was making the return journey to Bucharest with a group of other Hoops fans who had travelled to Razgrad for the Champions League qualifier v Ludogorets on Tuesday night,” the statement reads.
"Daniel Fulham is a long-standing club member and volunteer who has made many international journeys in his working and social life with the same passport as was presented to the border police.
"It is understood that the authorities questioned the validity of the photograph in matching Daniel's identity.
“The Department of Foreign Affairs are liaising on the matter in which there is no doubt about the validity of the passport, and we hope to see the matter closed as quickly as possible for Daniel to return home.
According to thejournal.ie, the group had flown into Romania and then got a bus from Bucharest to Razgrad around 140km away, with Ray Whelan who was with them.
Speaking to The Journal, Ray said there were no issues at all crossing into Bulgaria but it was the return journey that caused the hassle.
He said: “We were all a group going over. We had 20 of us or thereabouts going to the game from Bucharest so we got a minibus. We had to go through Romania into Bulgaria – getting into Bulgaria was no problem.
“We went to the match and then were getting the bus back across the border. The border guard got on and took everyone’s passports, which is sometimes what happens on trips like these.
“Then they called Dan off. We thought they just designated him as the fella they were going to give all the passports back to but then we realised there was an issue.”
Ray explained that they were “pinning his ears back in front of him trying to distort his face to make him look like the photo in his passport”.
Ray said the bus was stopped for two hours and Dan was finally told he was to be arrested and detained as they believed he was not travelling on a legitimate passport.
Ray added: “The last we heard is that the Bulgarian prosecutor is still not believing it’s him despite the Irish authorities saying it’s a legitimate passport.”
TDs have been calling for the Government to get involved.
Daniel’s mother, Noeleen Fulham, has also called on Simon Coveney to intervene.
The Department of Foreign Affairs said it is working with Bulgarian authorities.
A spokesperson said: “The Department of Foreign Affairs is aware of reports and is providing consular assistance. As with all cases, the Department does not comment on the details of any specific case.”