Mr Stuart (24) was runner-up in the national final held at the recent Canterbury A&P Show.
Sam Westenra, of Marlborough, won the event, while Josh Kirk (Canterbury) was third and Liam Dundass (Marlborough) fourth.
Mr Stuart, who qualified for the final at a junior judging day held in October at Malvern Downs, Tarras, has competed in the national final about four times.
Last month’s placing was the best he had achieved and, keen to win the competition, he was likely to have another crack at it, he said.
He first entered the Mackenzie competition when he was a teenager living at high country property Tara Hills, at Omarama, which was then managed by his father Greg. He was keen to have something on his CV and also to learn more about merino sheep.
Hamish and Andrew Jopp later got him back into it when he was working at Moutere Station, near Alexandra, and schooled him up, while he had also received a lot of coaching from Allan and Simon Paterson, of Gimmerburn.
The competition involved placing four merino sheep in order and then speaking about the reasons for the placings.
While people often thought the public-speaking part was the hardest bit, he had found it to be beneficial and he no longer got so nervous now that he knew what he was doing.
The competition is open to young people aged 25 and under and Mr Stuart encouraged others to have a go, saying it was definitely a good way to learn.