Welp, Duffy suffered a mild concussion and has been ruled out of the fight. No replacement
The UFC's statement can be seen below."Due to a medical issue involving UFC lightweight Joe Duffy, the new main event of UFC FIGHT NIGHT in Ireland on Saturday will be a three-round bout featuring hometown hero Paddy Holohan vs. Louis Smolka.
"Having learned that Duffy received a strike to the head during training earlier this week, UFC sent him for medical tests in Ireland for precautionary purposes. The results determined that Duffy suffered a mild concussion and due to the proximity of the fight this Saturday UFC will not permit him to compete. The health and safety of UFC athletes will continue to be the top priority for the organization. As such, UFC has respected standard athletic commission regulations, which recommend a medical suspension from competition as a result of the concussion.
"Duffy's original opponent, Dustin Poirier, will be rescheduled for another event. Fans seeking ticket refunds as a result of the main event changes can do so through Ticketmaster at the point of purchase."