Barclays Center Bus Attack (UFC 223 media day)

On April 5, 2018 during UFC 223 media activities at Barclays Center in Brooklyn, Conor McGregor and a group entered the arena loading-dock area and confronted buses transporting fighters to the venue [1]. Video and eyewitness accounts show McGregor throwing a metal equipment dolly through the window of a bus transporting lightweight contender Michael Chiesa and other fighters; ESPN reported "When the Irishman threw a steel dolly through the window of a bus carrying the fighter he was targeting, lightweight champion Khabib Nurmagomedov, as well as several other fighters and UFC staff -- some of whom were injured in the attack -- there was the crime" [1]. Multiple fighters sustained cuts; Michael Chiesa and Ray Borg were among those who withdrew from UFC 223 as a result of injuries sustained or related concerns, forcing card changes for the April 7 event [1]. UFC president Dana White described the incident immediately afterward, calling it "the most disgusting thing that has ever happened in the history of the company," and New York authorities investigated the event as a backstage melee and property damage incident [1]. The event produced extensive video evidence circulated by media outlets and prompted security and legal scrutiny at the time; the altercation became a central episode in the McGregor–Nurmagomedov escalation sequence and was cited repeatedly in later reporting and legal filings [1][7].

The April 5, 2018 Barclays Center bus attack materially escalated the McGregor–Nurmagomedov dispute from verbal and small-scale altercations into an overtly criminally investigated act of property destruction and assault [1][2]. It caused injuries that altered UFC 223's fight card, drew condemnation from UFC leadership, and established a documented grievance that Khabib's camp and others cited in the promotional buildup to UFC 229; the attack also led to legal consequences for McGregor and later civil litigation by injured fighters [1][2][8]. As a documented physical act tied directly to team allegiances, the bus attack became a defining piece of evidence in the narrative of retaliation and retribution between the camps.

Following the April 5 bus incident, the New York Police Department and other entities investigated; Conor McGregor ultimately pleaded guilty to a single count of disorderly conduct in Brooklyn on July 26, 2018 in connection with the episode, receiving five days of community service, an anger-management evaluation and restitution as part of the disposition [2]. Michael Chiesa filed a civil suit in September 2018 alleging negligence, emotional distress, assault and battery; that civil matter was later discontinued via settlement on December 2, 2022 [8]. The bus attack remained a frequently cited provocation during the promotion for UFC 229 and formed part of the factual record that reporters used to explain why tensions between McGregor and Khabib had escalated [1][8][9].