His times were 17.5 seconds in the heats, 17.2 in the semi, and then 16.3 in the final, he said.
The close finish against Taiki sent the crowd wild, as the Australian shore his 16.6 timing, second to last before Fagan, he said.
"I happened to go 16.3 and the entire stadium just erupted."
Fagan said he shore "tiny little" Welsh Beulah Speckled-Face lambs and he reckoned the world record for the event "floats around the 14-second mark".
It was a sweltering 30 degrees plus in Wales on Sunday night when Fagan spoke to Mackay and he said the temperature was expected to rise even higher the following week.
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The heat wouldn't deter attendees at the Royal Welsh Show, which had been cancelled for the past two years due to the pandemic.
"It's 40-odd degrees I think it's going to be later on in the week and the Welsh are ready for a hell of a good show – the first one since 2019."