The stunning demand for pay-per-view telecasts of the Manny Pacquiao-Floyd Mayweather mega-fight had providers struggling to meet it on Saturday.

The start time for the pay-per-view telecast, which included two undercard bouts, had come and gone in the United States and complaints had surfaced on Twitter, that in some areas cable providers were unable to deliver the show.

The scale of the problem was enough to have telecasters Showtime and HBO hold up the main event for about 45 minutes.

Problems ranged from issues with ordering, to pixellated screens, to screens going to black after the broadcast had started.

"We are aware of the issue impacting the Mayweather vs. Pacquiao feed," US cable provider Charter Communications tweeted.

"We are working to resolve as soon as possible."