The highly anticipated fight between Floyd Mayweather and Conor McGregor was officially delayed shortly before its scheduled starting time due to widespread technical issues preventing an unspecified number of paying subscribers from being able to watch live.

Showtime issued a statement acknowledging the problems and announcing the delay late Saturday. “Due to high demand, we have reports of scattered outages from various cable and satellite providers and the online offering. We will delay the start of the main event slightly to allow for systems to get on track. We do not expect a lengthy delay.”

After initial indications the main event would commence at 11:15 p.m ET, it didn’t get started until nearly one hour later.

The delays are an embarrassing and perhaps costly interruption for one of the biggest sports events of the year. Social media was bombarded with complaints from fans who paid $100 to get the pay-per-view telecast of the fight only to get error messages and no live stream of the action. Hours into the 9 p.m. ET telecast, UFC acknowledged the issues in a tweet: “Due to overwhelming traffic you may be experiencing log in issues. This will be resolved shortly.”

However, it didn’t appear any resolution was found as hundreds complained about being blocked from accessing the fight they paid for via myriad methods, from traditional multi-channel pay-per-view to streaming directly from UFC Fight Pass, regardless of device.

College basketball commentator Dick Vitale, for instance, railed against cable operator Frontier Corp. when a party he was attending was disrupted by an inaccessible PPV. “Yes @FrontierCorp has zeto concern for their customers / I am livid / planned all week for our fight party / what a nightmare/Thnx Frontier,” he tweeted.

Piracy was also evidently a problem as streams of the fight from subscribers who had no trouble accessing the event were broadcast via livestreaming apps such as Twitter’s Periscope to users who didn’t have to pay to watch a live albeit grainy feed.

Mayweather-McGregor was expected to be among the biggest PPV draws in history, estimated to reap as much as $1 billion in revenues. But the total haul from the event could be impacted if refunds have to be delivered to a significant subset of the audience.