It was his first full-wool competition, the first where he could test his skills throwing the fleece onto the table.
His own assessment: "Alright."
But Nanna Rose was impressed, saying: "He had just one shot. His fleece was good, he placed it and walked back, it was beautiful placement."
Already a student of the sport's rulebook, the competitive intent was obvious, a strength his nanna says comes from his rugby and now rugby league, where it helps his father is one of the coaches.
Event over, Cortez then had to wait through other heats to see if he would qualify for the final in the afternoon, the first of 19 titles to be decided at this year's Golden Shears.
Alas, of the 27 in the novice woolhandling heats, Cortez Ostler was 10th, missing the cut for the semifinal by two places.
Qualifiers were: Chiara Kirikiri (Masterton), Catherine Mullooly (Matawai), Ronald Eria (Hastings), Dayna Rutene (Masterton), Linton Palmer (Dipton), Cheyenne Walker (Masterton), Ricci Stevens (Napier and Gisborne), Samantha Pritchard (Pongaroa)