Definition: In this task, you will be presented with a passage and have to answer a question based on your understanding of the events inferred from the passage. Try to find the best answer that is most likely to fill in "_". Note that the URLs in the text have been replaced with [Link].
Input: Conor McGregor and Chad Mendes were unable to complete the traditional face-off on Friday night as the simmering tension between the pair reached boiling point. Mendes stepped in for the injured champion Jose Aldo at less than three weeks' notice but weighed in half a pound under the 145lb featherweight limit in Las Vegas. McGregor, who was roared on by the large contingent of Irish fans among the record 11,000 who attended the weigh-in, made the weight exactly. But UFC president Dana White had to keep the two at arm's length as the fight threatened to break out 24 hours early.Conor McGregor takes on Chad Mendes in Las Vegas on Saturday nightThe Irishman was due to face Jose Aldo but he pulled out with a rib injuryMcGregor and Mendes almost came to blows at the weigh-in on FridayThe 26-year-old faces a career-defining night against Mendes 
 Question:He also posted on Instagram: 'I've seen crack heads roaming the street that look healthier than McGregor right now', in reference to the _'s gaunt appearance.

Irish