After providing three assists in his first four games since arriving from Yokohama F Marinos, Mizunuma grabbed his first goal in Jets colours in the 21st minute on Friday evening at McDonald Jones Stadium, ending a slick passage in which the hosts sliced across the Roar's penalty area.
"I'm very happy, but I want to go to the next level," Mizunuma told Paramount.
Eli Adams' fourth goal of the campaign doubled the lead in the 38th minute and while a thunderous long-range free kick from Jay O'Shea gave the Roar hope at halftime, this was snuffed out five minutes after the break when Clayton Taylor snatched a Callum Timmins effort off the post and fired home.
"We want to make finals," Newcastle's Lachie Rose told Paramount.
"Everyone underestimated us at the start of the year.
"Now we've got that togetherness where we've got to fight to the end."
Unbeaten since Mizunuma's arrival - a five-game run that's their longest unbeaten stretch in three years - the Jets climbed out of the league's bottom three for the first time since November, vaulting ahead of Wellington and arch-rivals Central Coast to ninth.
It also moved Rob Stanton's side within four points of the playoff places.
"He plays like a 17-year-old, and that's the energy he brings to the training," Rob Stanton said of Mizunuma.
"When players see that, the penny starts to drop. That's what a top pro looks like. They get belief because he's a winner.
"For someone to want to come here and bring that and buy into Australian culture and Newcastle, it's tremendous."
Suffering their 12th defeat of the campaign, the Roar remain rooted to the foot of the ladder with 10 games left in their campaign, four points behind eleventh-placed Perth having played two fewer games.
Ruben Zadkovich's side had started the contest positively, only to be brought undone when the Jets scored from their first meaningful attack.
"We just weren't good enough tonight," Zadkovich told Paramount.
"The Jets were a little bit too good for us, and we have to be at our best to win with what we have."
