Gangster 'Fat' Freddie Thompson has been released from prison, sparking fears of an increase in tensions in criminal circles in the capital.
The 34-year-old served a 15-month sentence for violent disorder after an attack on another man at Morrissey's Pub on Cork Street, in Dublin, on January 7, 2013.
He was extradited from Amsterdam in May of last year and received a 20-month sentence for his involvement in the vicious brawl.
In February he admitted the charge, which the court heard was sparked by a slagging match. Thompson reacted to taunts by throwing a punch and a bottle.
He walked free from Mountjoy Prison on Saturday because he had already spent nine months in custody while on remand.
However, sources have said that the underworld boss is not welcome back in Spain's Costa del Crime by his former associates in the cartel run by Christy Kinahan.
One source said they now consider him a liability to their operation.
He is therefore more likely to stay in Dublin, which will be a headache for gardai, who fear he may cross swords once more with rivals from his past.
Sources have revealed that the gangster will be closely monitored by gardai now that he is back in circulation.
"One thing you can say about Thompson is that the situation is always much more fraught when he is around the place," a source said.
"What happens is you have young fellas going around trying to impress him and then you have his rivals seeking him out to kill him.
"To say that Freddie is a general nuisance would be a complete understatement," the source added.
A potential flashpoint that detectives will be monitoring is whether Thompson will go head-to-head again with his hated rival Declan 'Whacker' Duffy, with whom he was involved in a high-profile feud in 2008 and 2009.
Duffy has been stepping up his lucrative extortion activities in Dublin's south inner-city in recent months.
Other potential rivals include associates of the drug gang headed by Brian Rattigan - who is serving life in Portlaoise Prison for the murder of Declan Gavin outside the Abrakebabra fast food restaurant in Crumlin in August 2001.
Thompson has been far from a model inmate and spent a number of weeks on a punishment regime in jail in Cork, where he was sent for his disruptive behaviour while in the Dublin prison.