Firas Zahabi: Joseph Duffy suffered concussion Saturday night

Joseph Duffy was forced to withdraw from his UFC Fight Night Dublin main event fight against Dustin Poirier due to a last-minute head injury.

According to Duffy's head coach Firas Zahabi, Duffy was injured Saturday evening -- seven days before the fight.

"He suffered a concussion on the last day of sparring," Zahabi wrote via text message to MMAFighting.com.

Zahabi, who said his fighters "always spar the week before" a fight, did not question the UFC's decision to remove Duffy from the fight. The UFC is serving as the athletic commission for Saturday's event because there is none in place in Ireland.

"Concussions are a serious thing, and I trust the doctor made the best call for Joe's health," Zahabi added. " A week is not long for a concussion to heal."

When contacted by MMAFighting.com, the Montreal-based Zahabi was on his way to the airport to catch a flight to Dublin to corner Tom Breese and Steven Ray. Amazingly, this will mark the long-time MMA coach's maiden voyage to Europe.

The UFC has yet to announce what they plan on doing next for both Poirier and Duffy. The new UFC Dublin main event is Paddy Holohan vs. Louis Smolka.