Dermot Laide and Sean Mackey were released from prison last night having completed their sentences for violent disorder.
Both were sentenced to two years' imprisonment in March 2004 in connection with the death of Brian Murphy outside Anabel's nightclub in Dublin in August 2000.
Laide (23), from Rossvale, Castleblayney, Co Monaghan, left Loughan House open prison in Co Cavan shortly after 10pm last night.
Mackey (24), from South Park, Foxrock in Dublin, was released from Shelton Abbey open prison in Co Wicklow at around 1am this morning.
Laide had also received a four-year sentence for the manslaughter of Mr Murphy, an 18-year-old student who died after being kicked and beaten.
However, last February the Court of Criminal Appeal quashed the manslaughter conviction, while upholding the conviction for violent disorder.
Next spring Laide faces a retrial on the charge of the manslaughter of Mr Murphy.