"It's massive because we have to get in there and help the forwards out in the tough times in the game," Fusitu'a told Radio Sport's D'Arcy Waldegrave.
"It takes a lot out of you when you're playing in the middle, so it has been a building block of my game, really getting in there and using my size, footwork and pace just to get front-foot ball and start off our sets well."
Since returning from an ankle injury in the round seven win over Canterbury, Fusitu'a's versatility has seen him feature on both wings, while he also played a starring role at fullback in the round nine win over St George Illawarra.
That display saw him win selection in the No 1 jersey for Tonga, making his international debut in last month's 18-6 Pacific test defeat to Samoa, and his confidence has continued to soar along with the Warriors' improved form.
His increased involvement has not gone unnoticed, with coach Andrew McFadden praising his willingness to mix it in the middle of the park.
"He's been getting better and better every week," said McFadden.
"He had some tough carries, got belted a few times as well.
"He's obviously very good at finishing things off but it was the rest of his game that I thought was probably the stand-out."
The Warriors are now looking for a third straight win in Sunday's clash against the Sydney Roosters at Mt Smart Stadium, but Fusitu'a is wary of a side coming off Saturday's 46-0 hiding against Melbourne.
"I don't know if it's a good thing they got pumped because they'll be coming out firing.
"We're just going to go back to training and make sure that we're up for a tough contest."
