They're keeping their spirits up ahead of the big night anyway.
The UFC's official Instagram posted a video in the early hours of this morning, which shows some enthusiastic Conor McGregor fans dancing... in the middle of a Las Vegas road.
The video went live yesterday evening local time, and was most likely filmed after the weigh-in for tonight's UFC 194 main event - the featherweight unification bout between McGregor and Jose Aldo.
The
weigh-in was preceded by a Holly Holm Q&A, which featured lots of enthusiastic Irish fans - some of whom serenaded
the new UFC women's bantamweight champion.
The party appears to have carried on out on the streets, with little care for the Las Vegas traffic.
https://www.instagram.com/p/_LY8yeJJfW/?taken-by=ufc
If the Irish keep "taking over" the public thoroughfares, the authorities may have to call in the cowboys to round them up.
The Wrangler National Finals Rodeo are on also taking place in the Nevada city this weekend, so if the rowdy Irish need to be corralled these could be the (cow)boys to do it.
https://twitter.com/afuelracer1/status/675463020760444928
