The quinella-makers launched big runs from the rear at the 800m before breaking away from their rivals and going head-to-head in an epic dual over the last 400m of the 2700m feature.
Cast No Shadow loomed up to Robyns Playboy in the straight, but the southerner would not be denied as he went on to score an impressive win for trainers Ross and Chris Wilson, and driver Craig Ferguson.
Good beginnings and positive driving have enabled the 4yr-old to land on the speed in most of his recent runs.
The Wilson stable went into yesterday's race with a different tactics, preferring their pacer to sit off the speed in the 10-horse field.
A fast first lap set up by the leader, Chiller Bay, allowed Ferguson to do exactly that, before Robyns Playboy zoomed around the field to win.
"We wanted to drive him with a sit today," Ross Wilson said.
"He has got a lot of speed.
"Last week [at Ascot Park] he wouldn't take the passing lane, because he is still learning.
"This week Chris was driving him in work at Gore and he took him up the inside where it was quite wet and he still ran a 26sec-quarter [400m]."
Robyns Playboy was nominated for the New Zealand Cup, but was withdrawn after his seventh in last month's Hannon Memorial at Oamaru.
The Wilsons will freshen the Shadow Play pacer, rather than aim him at other races at the New Zealand Cup carnival such as the junior free-for-all.
"I think we will give him a break. He has had a few hard runs now," Ross Wilson said.
"We will get him ready for the Central Otago Cup. There are plenty of good races coming up. He could even have a go at the Gore Cup before then."
Robyns Playboy held out Cast No Shadow by a length and a-quarter at the line.
Bettathanfast went a sound race for third, a further three and a-half lengths away, after sitting parked throughout.
Another highly exciting last 400m played out when Stun Gun launched an attack from the rear of the field on the leader in race 5, Spirit Of St Louis.
The pair went head-to-head before the home turn after Stun Gun sprinted quickly to put his nose in front at the 400m.
Spirit Of St Louis regained the lead in the straight before shaking off Stun Gun's challenge.
The 3yr-old went on to win by a length and a-quarter from Deus Ex, who also rallied to hold out Stun Gun.
Spirit Of St Louis ran a sensational closing split, clocking his last 800m in 56.3sec and final 400m in 26.9sec.
His Westwood Beach trainer, Graeme Anderson, said he would freshen Spirit Of St Louis before making any plans for the horse's next start.
The 2019 Tuapeka Cup meeting will be one to remember for Kimberly Butt.
The West Melton horsewoman scored her first victory as a trainer when Lennox Bromac sprinted along the passing lane to win race 3.
The win was made more special because Butt's fiance, Jonny Cox, drove her first winner.
Butt's maroon and white colours, with their chequered sash, are a tribute to the line of talented trainers she descends from. The maroon and white on her silks were inspired by her father Anthony's colours. The addition of a chequered sash links her colours to those of her grandfather, former trainer Dick Prendergast.
