Kopua attended to unfinished business in style on the middle day of the New Zealand Cup carnival at Riccarton when he produced an irresistible finish to claim top honours in the main event on the card.

The son of Shocking had finished a luckless sixth in the Gr.3 Coupland's Bakeries Mile (1600m) 12 months ago and successfully turned his fortunes around in Wednesday's feature, now renamed the TAB Mile.

Kopua further added to the long list of Riccarton successes of his trainer Kevin Myers, who has regularly placed his faith in younger riders and this time the recipient was last season's champion apprentice Lily Sutherland.

"It was a great ride by Lily to get over the top of them," Myers' son Jason said.

"It's great for her to get a big race, Lily is an extremely hard worker and she's just improving all the time."

Kopua  was fourth up in his preparation and had won an open handicap at Taupo three runs back before he finished third at Riccarton last month and the step to 1600m proved ideal.

Despite his lead-up form, the seven-year-old was unwanted in the market.

"We thought $25 was well over the odds and we'd been quietly confident with him, he was very unlucky in the race last year," Myers said.

Kopua settled well back in the field and when the field swung for home he was in behind a wall of horses.

Sutherland kept her cool admirably and as runners fanned across the track, she got to work on her charge who responded so positively to mow his rivals down for the eighth victory of his career.

"They have just been so supportive of me and it's so good to ride a big winner for the family," she said.

"We got squeezed up a bit early, but he travelled really well into the race."

Bred by Marie Bloodstock, Kopua is part-owned by Kevin Myers who has enjoyed previous successes with the family having prepared Yanna Marie to win both the Gr.3 Cuddle Stakes (1600m) and the Listed Ag Challenge Stakes (1600m).

The pedigree page also features the Gr.1 Winfield Classic (1500m) winner Achushla Marie and the Gr.1 Emirates Stakes (1600m) winner Hucklebuck.

Kopua's resolute finish got the better of Matscot to deny his rider Michael McNab a feature race double after successfully combing with Acquarello in the Gr.3 Windsor Park Stud Canterbury Breeders' Stakes (1400m).

Third home was the Te Akau stalwart Perfect Scenario, who earned a gold star for bravery under his topweight of 60kg, conceding the first two home 7kg and 5.5kg respectively.