Floyd Mayweather Jr. weighed in for his hugely anticipated fight with Conor McGregor at 149.5 pounds, well under the 154lb limit.

Mayweather was expected to be far lighter than McGregor on fight night but was already 3.5lbs off his opponent on Friday, the Irishman having tipped the scales ahead of his professional boxing debut at 153lbs.

An animated McGregor then faced off with to the 40-year-old, who remained calm while the UFC star barked just inches from his face.

Mayweather – boasting 49-0 throughout his boxing career – appeared unconcerned by his weight in an on-stage interview, reiterating his feeling the fight will not go the distance and stating his opponent will not return to the ring.

"I've been here before. I know what it takes when it's a fight of this magnitude. Weight doesn't win fights, fighting wins fights. It won't go the distance, mark my words," he said.

"I just want to thank the fans. I'm not worried about the scales or [it being] the last time. This will be Conor McGregor's last fight also."

McGregor, who received the support of the majority of the spectators, appeared typically confident and expects to be close to a stone heavier when the pair enter the ring at the T-Mobile Arena on Saturday.

He said: "I'm gonna breeze through him. I'm a professional, I make weight. Look at me, I'm in peak physical condition. I've put in the work as everyone can tell.

"[I'll be] a lot bigger, a lot bigger than him. I'd say close to 170. I'll stomp my foot right in the centre of that ring and I won't move. I see a man afraid."