Booth judged six of 12 fights, including the main event, at the UFC show in Manila at the weekend.
The Dunedin labourer was part of a six-strong New Zealand team that officiated, but he and Hamilton's Mark Craig were the only ones to judge.
Booth (52) described the experience as ''surreal'' and said there were several moments when he had to pinch himself to believe he was working with the ''massive UFC machine''.
''It was interesting to just be involved and see how well-run the big show is,'' Booth said.
Sitting beside the octagon and watching his monitor while being within touching distance of the fighters, and both meeting announcer Bruce Buffer and hearing his name being called out, were experiences to treasure, Booth said.
Booth said he felt no nerves, because he was there to do a job. He treated it like any other fight, although he had to buy a suit.
In his first four fights, Booth did not have to give a decision, because they ended in finishes, but the two main fights both went to the judges.
In the co-main event, one of MMA's gentlemen bowed out in style as American Filipino Mark Munoz (37) ended his career when he beat Luke Barnatt by unanimous decision.
To see Munoz in his final was a highlight, and his farewell speech afterward was moving and ''highly emotive'', Booth said.
Frankie Edgar beat Urijah Faber by unanimous decision in the featherweight main event.
Because of his role, Booth was not allowed to get photos or interact with the fighters. While he saw plenty of MMA stars, he did not mind steering clear of them because he was a believer in not ''killing off your idols''.
He would gladly accept any future UFC appointments, but his immediate plans were to referee Saturday's Hammerhead Productions show in Dunedin.
Booth said the New Zealand team's involvement in Manila had a lot to do with the formation and governance of the New Zealand Mixed Martial Arts Federation.
Federation president Terry Hill refereed four fights at the Manila show.
Hill described it as a ''huge thrill'' and said to have six New Zealanders working at a UFC show spoke highly of the competency of the organisation.
The officiating came about because of the work done by NZMMAF vice-president Nyra Phillips and her role in Las Vegas as the IMMAF world championships tournament co-ordinator.