It was a memorable night for Magpies rugby prop Long who also won the first two heats in a 17-strong class and could have won the third but appeared to let Lion Jon Brown have the win.
McLachlan didn't see the final heat but was impressed with what Long did earlier in the night.
"Jason is at the top of his game and we've come to expect those sort of drives from him."
The Meeanee Maulers stockcar team was also in celebration mode after winning the Rees Shield for the first time with a victory against the Rotorua Rascals.
Maulers Brandon Symes and Cameron Swift were first and second early. Rascal Shannon Orr only lasted two laps after taking a huge hit.
Swift secured the win, Symes was second and Sheldon Arapere was the only Rascal to complete all 10 laps on the way to third place. The Rascals got their revenge in the second race between the two teams when Dion Henderson secured the chequered flag.
Maulers manager Andrew Powell said after the shield was won he used the second race to try drivers in different roles so they could build experience.
"I was pretty confident we could win the shield. We've got a fair bit of ability and it showed."
His five drivers used on Saturday night, Swift, Symes, Brett Loveridge, Daniel Melling and Andre Stenson, will form the squad for their national teams champs in Stratford later this month with Regan Penn expected to take the sixth driver role.
Hawke's Bay drivers won all three heats in the 21-strong stockcar class. First-season driver Zayne Pullen posted his first victory when he won the feature while Ben Milne and Craig McBeth won the other two.
Hawke's Bay-based Australian motor racing commentator Greg Rust raced Gisborne driver Ryan MacGregor's TQ in the first race for this 11-strong class and did well to finish seventh and avoid the car flipped by first-season driver in the class, Hawke's Bay's Ryan Dorward. Hawke's Bay's two-time national champion Duane Todd won two of the heats in this class and his clubmate Tony Meechan took out the other.
Hawke's Bay's Tim Towler won two of the three heats in the 12-strong streetstock class and his clubmate and former 3NZ Brent Redington pipped him in the other.
Host track driver Bailey Smith won two of the three heats in the 21-strong ministock class and clubmate Trent McCann had the victory lap in the other.